Answered: Why are compounds composed of integer…

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

See similar textbooks

Related questions

Concept explainers

Question

Back ground info:

Atoms of different elements combine with one another to form compounds. It is important to be able to explain how atoms actually come together to form these compounds or chemical bonds. One of the three types of bonds is an ionic bond which is a bond between a metal atom and a nonmetal atom, or a cation and an anion. The Octet Rule is the driving force behind ionic bond formation.

The octet rule refers to the tendency of atoms to prefer to have eight electrons in the valence shell. When atoms have fewer than eight electrons, they tend to react and form more stable compounds. When discussing the octet rule, we do not consider d or f electrons. Only the s and p electrons are involved in the octet rule, making it useful for the main group elements (elements not in the transition metal or inner-transition metal blocks); an octet in these atoms corresponds to an electron configuration ending with s²p⁶.

One way an atom can satisfy the Octet Rule is by transferring valence electrons from one atom to another. Atoms of metals tend to lose all their valence electrons, which leaves them with an octet from the next lowest principal energy level. Atoms of nonmetals tend to gain electrons in order to fill their outermost principal energy level with an octet. This transfer of electrons from a metal to a nonmetal creating ions, is how an ionic bond is formed. This bond is held together by electrostatic attraction, or the attraction between the positive and negative ions in the bond. Although the ions are charged in an ionic bond, the net result of the bond will be zero.

Scientists like to use pictures to help explain scientific phenomenon. We will learn to draw a picture to help explain how ionic bonds are formed. One way to model ionic compounds is using Bohr models similar to the ones drawn below. But, drawing out the whole Bohr model takes up a lot of space and can be time consuming to draw, so instead we make simplified little models called Lewis dot structures that have only the atomic symbol and the valence electrons.

The rest of the background info will be provided in a picture.

Scientific question: Why are compounds composed of integer ratios of elements?

Hypothesis: If an atom ionizes to become a positive cation, then it will interact and bond with a negative anion to form an ionic bond.

Two simulations that were used are below:

This activity is structured as a game, wherein your challenge is to create correct ionic compound formulas by combining individual ions based on their charges. Once you correctly connect the atoms in the interactive website, a common use for that compound will be revealed. In this worksheet, you must record both the correct formula for each of the seven ionic compounds and their common uses as revealed by the interactive program.

Throughout the activity, you will have the option of skipping each compound – if you choose to do this, its common use will not be revealed. You must correctly write the formulas and match the common uses.

Website for first simulation: https://www.learner.org/wp-content/interactive/periodic/bonding

Click “Begin” on the first page you see.
For each compound name listed at the top of the interactive, choose the correct cation and anion which you think belong to the formula for that compound.

For example: Sodium Chloride, click “Na⁺” and “Cl^-“.

3. Drag one ion on top of the other until the two ions you want to connect are highlighted yellow. We recorded this info in a table.

The second/last simulation:

Open the following website: https://javalab.org/en/ion_model_en/

Use the puzzle pieces to form the ionic compounds listed in data table 2, and then fill in data table 2 with that information. Write the formula for that compound and draw or copy and paste your completed puzzle for each ionic compound into the table.

This is the actual question you will answer. The info above is info you will need to answer the question.

Present the scientific question to inform the audience of the goals related to your research. Cite the sources used in the study, both text and technology, noting how they advanced your understanding. Introduce the hypothesis. Overview high level results. Provide a one sentence summary of what you learned. Example of how to answer this is attached.

**Background Info on Lewis Dot Structures and Polyatomic Ions**

**Lewis Dot Structures:**
Lewis dot structures were invented to help represent the valence electrons in an atom. Each dot in a Lewis Structure symbolizes a valence electron, marked with the element's atomic symbol. To draw one, start with the atomic symbol in the center, then place dots around it until all valence electrons are depicted. Dots are drawn on each side before pairing them. The maximum pairs per side is two, and the total valence electrons should complete the atom's outer shell, generally achieving stability with eight electrons.

**Periodic Table and Valence Electrons:**
The periodic table helps determine the number of valence electrons for elements, especially those in the main groups. The group number often indicates the number of valence electrons.

**Diagram Explanation:**
- The image shows a periodic table color-coded by groups, highlighting the organization of elements based on similar properties.
- The adjacent diagram illustrates a chlorine atom's valence shell configuration.

**Modeling Ionic Compounds:**
To model ionic compounds using Lewis dot structures:

1. **Step 1: Formation of Ions**
- Ions often form from elements on the periodic table. Monatomic ions (like Cl⁻) stem from single atoms gaining or losing electrons.
- Example: Na → Na⁺ and Cl → Cl⁻

2. **Step 2: Polyatomic Ions**
- Polyatomic ions consist of multiple atoms with a specific charge. Understanding them involves counting total valence electrons across the atoms.

3. **Step 3: Modeling Chemical Bonds**
- Illustrations demonstrate the transfer and sharing of electrons in ionic bonding (e.g., between Al and Cl).

**Understanding Polyatomic Ions:**
Certain ions encompass multiple bonded atoms with an overall charge, crucial in forming diverse compounds. Awareness of common polyatomic ions aids in chemical formula identification and reaction prediction.

**Common Polyatomic Ions List:**
- NH₄⁺ (Ammonium)
- C₂H₃O₂⁻ (Acetate)
- CO₃²⁻ (Carbonate)
- OH⁻ (Hydroxide)
- NO₃⁻ (Nitrate)
- SO₄²⁻ (Sulfate), etc.

**Tips for Writing Chemical Formulas:**
1. Use parentheses for multiple polyatomic ions in a formula.
2. Ensure the total ionic

**Global Statement**

*Present the scientific question to inform the audience of the goals relevant to your investigation.*

The research and experimentation conducted in this lab helps answer the following scientific question, "How does the percent abundance of isotopes affect the average atomic mass reported for a specific element?"

**Introduce Research**

*Cite the resources used in the study, both text and technology, noting that they advanced your understanding.*

A supplied text and the Isotopes and Atomic Mass simulation from PhET Interactive Simulations were used to collect background research and data to answer this scientific question.

**Thesis Statement**

*Introduce the hypothesis you predicted. If your preliminary answer to the scientific question is what you used to design the experiment.*

Furthermore, the information gathered with the labs aids in figuring out if the following hypothesis was accurate, "If I increase the percent abundance of the hydrogen-1 isotope using a computer simulation (since percent abundances are natural and cannot actually be changed), then the average atomic mass of the hydrogen element will also increase."

**Overview High-Level Results**

*Provide a one-sentence summary of what you learned from the study.*

The experimental data demonstrated that, as the abundance of hydrogen-1 isotope increases, the average atomic mass of hydrogen DID NOT increase. Instead, it decreased. More specifically, it was found that the average atomic mass will be similar to the mass number of the most abundant isotope.

Expert Solution

Trending now

This is a popular solution!

Step by step

Solved in 3 steps with 3 images

SEE SOLUTION Check out a sample Q&A here

Knowledge Booster

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.