The given statement concerning 2-butene has to be identified as true or false. Concept Introduction: Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula. Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally. Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water. Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density. Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature. When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms. Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

Question

Want to see the full answer?

Answer 1

Question

Definition Definition Molecules that have multiple bonds between their carbon atoms. Alkenes are hydrocarbons with a double bond between two adjacent carbon atoms (R 2 C=CR 2 ), whereas alkynes are hydrocarbons with a triple bond between two adjacent carbon atoms R-C=C-R . These two groups are known as unsaturated hydrocarbons. They have fewer hydrogen atoms when compared with alkanes with same number of carbon atoms. The general molecular formula for an unsaturated hydrocarbon can be represented as C n H 2n +2 .

Chapter 13, Problem 13.61EP

(a)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(b)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(c)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(d)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Students have asked these similar questions

None

n Feb 3 A T + 4. (2 pts) Draw the structure of the major component of the Limonene isolated. Explain how you confirmed the structure. 5. (2 pts) Draw the fragment corresponding to the base peak in the Mass spectrum of Limonene. 6. (1 pts) Predict the 1H NMR spectral data of R-Limonene. Proton NMR: 5.3 pon multiplet (H Ring

Part VI. Ca H 10 O is the molecular formula of compound Tom and gives the in the table below. Give a possible structure for compound Tom. 13C Signals summarized C1 C2 C3 C4 C5 C6 C7 13C shift (ppm) 23.5 27.0 33.0 35.8 127 162 205 DEPT-90 + DEPT-135 + +

Answer 2

Question

Definition Definition Molecules that have multiple bonds between their carbon atoms. Alkenes are hydrocarbons with a double bond between two adjacent carbon atoms (R 2 C=CR 2 ), whereas alkynes are hydrocarbons with a triple bond between two adjacent carbon atoms R-C=C-R . These two groups are known as unsaturated hydrocarbons. They have fewer hydrogen atoms when compared with alkanes with same number of carbon atoms. The general molecular formula for an unsaturated hydrocarbon can be represented as C n H 2n +2 .

Chapter 13, Problem 13.61EP

(a)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(b)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(c)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(d)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Answer 3

Question

Definition Definition Molecules that have multiple bonds between their carbon atoms. Alkenes are hydrocarbons with a double bond between two adjacent carbon atoms (R 2 C=CR 2 ), whereas alkynes are hydrocarbons with a triple bond between two adjacent carbon atoms R-C=C-R . These two groups are known as unsaturated hydrocarbons. They have fewer hydrogen atoms when compared with alkanes with same number of carbon atoms. The general molecular formula for an unsaturated hydrocarbon can be represented as C n H 2n +2 .

Chapter 13, Problem 13.61EP

(a)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(b)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(c)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(d)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Answer 4

Question

Definition Definition Molecules that have multiple bonds between their carbon atoms. Alkenes are hydrocarbons with a double bond between two adjacent carbon atoms (R 2 C=CR 2 ), whereas alkynes are hydrocarbons with a triple bond between two adjacent carbon atoms R-C=C-R . These two groups are known as unsaturated hydrocarbons. They have fewer hydrogen atoms when compared with alkanes with same number of carbon atoms. The general molecular formula for an unsaturated hydrocarbon can be represented as C n H 2n +2 .

Chapter 13, Problem 13.61EP

(a)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(b)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(c)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(d)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Answer 5

Chapter 13, Problem 13.61EP

(a)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(b)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(c)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

(d)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

Answer 6

Chapter 13, Problem 13.61EP

(a)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

Answer 7

Chapter 13, Problem 13.61EP

(a)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

Answer 8

(b)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

Answer 9

(b)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

Answer 10

(c)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

Answer 11

(c)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

Answer 12

(d)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

Answer 13

(d)

Interpretation Introduction

Interpretation:

The given statement concerning 2-butene has to be identified as true or false.

Concept Introduction:

Organic compounds are represented shortly by the molecular formula and structural formula. Each and every compound has its own molecular formula. Compounds can have same molecular formula but not same structural formula.

Alkenes are linear chain unsaturated hydrocarbons and cycloalkenes are cyclic carbon chain unsaturated hydrocarbons. They both occur naturally.

Alkenes and cycloalkenes are hydrocarbons. They are nonpolar molecules. Water is a polar molecule. Therefore, alkenes and cycloalkenes do not get solubilized in water. In other words, alkenes and cycloalkenes are insoluble in water.

Regarding density, alkenes and cycloalkenes have density lower than water. When alkenes and cycloalkenes are mixed with water, two layers are formed which is a result of insolubility. Alkenes and cycloalkenes are present on top of water layer which is due to lesser density.

Boiling point of alkenes and cycloalkenes increase with an increase in carbon‑chain length or the ring size. The continuous chain alkenes which contain two to four carbon atoms are gases at room temperature. The continuous chain alkenes that contain five to seventeen carbon atoms and one double bond are liquids at room temperature.

When branching happens in the carbon chain, it lowers the boiling point of alkenes. In simple words, unbranched alkenes have more boiling point than branched alkenes with the same number of carbon atoms.

Cycloalkenes have more boiling point compared to noncyclic alkenes with the same number of carbon atoms. This is due to the more rigid and more symmetrical structures that occur in cyclic systems. Cyclopropene and cyclobutene are relatively unstable compound and gets converted into other hydrocarbons.

Answer 14

Expert Solution & Answer

Answer 15

Expert Solution & Answer

Answer 16

Want to see the full answer?

Check out a sample textbook solution

See solution

Answer 17

Ch. 13.1 - Prob. 1QQ Ch. 13.1 - Prob. 2QQ Ch. 13.1 - Prob. 3QQ Ch. 13.2 - Prob. 1QQ Ch. 13.2 - Prob. 2QQ Ch. 13.2 - Prob. 3QQ Ch. 13.2 - Prob. 4QQ Ch. 13.3 - Prob. 1QQ Ch. 13.3 - Prob. 2QQ Ch. 13.3 - Prob. 3QQ

Want to see the full answer?

Chapter 13 Solutions