
Indicate which one of the two species in each of the following pairs is smaller: (a) Cl or Cl−; (b) Na or Na+; (c) O2− or S2−; (d) Mg2+ or Al3+; (e) Au+ or Au3+.
(a)

Interpretation:
In the given set of species which will be smaller in size has to be identified.
Concept Introduction:
- The distance between the nucleus and the valence shell of a cation or an anion is known as ionic radius. An ion is formed by either loss or gain of electrons from its valence shell.
- As we move down the group in periodic table the ionic radius increases as the electrons are added to new subshell. As we move across the period the ionic radius increases as the electrons are added to the same subshell.
- An anion is formed when an electron is added to the valence shell of an atom. The anion has a net negative charge in it. In anion the extra electron added occupies more space and maximizes the shielding.
- Anions will have larger size compared to cations.
- The reduction in the effective nuclear charge on the electron cloud, due to a difference in the attraction forces of the electrons in the nucleus is known as shielding effect
- When the proton number is greater than the electron, the size of the ion will be smaller due to less shielding. When the proton number is lesser than the electron, the size of the ion will be larger due to more shielding.
- A cation is formed when an electron is lost by an atom from its valence shell. The cation has a net positive charge. In cation the shielding decreases as the electron is removed from the valence shell.
- If the total number of electrons is less than the total number of protons in the ion, then the protons present can effectively attract the valence shell decreasing the size of the ion and vice-versa.
- The trend in periodic table can be described as well. As we move down the group the ionic radius decreases as the electrons are added to a new shell. But as we move across a period in periodic table the ionic radius increases as the electrons are added to the same subshell.
Answer to Problem 8.43QP
In (a)
Explanation of Solution
The number of electrons and protons in the given set of species (a) is,
Species | Total number of Electrons | Total number of Protons |
17 | 17 | |
18 | 17 |
The total number of electrons and protons present for the given species are found out and presented in the above table. From this we can see that total number of protons in all the given species is same, but the total numbers of electrons are different.
By comparing the total number of protons and electrons in the table given in the previous step and as comparing to the size of atom size of anion is larger. And also here the proton number is lesser than the electron in
(b)

Interpretation:
In the given set of species which will be smaller in size has to be identified.
Concept Introduction:
- The distance between the nucleus and the valence shell of a cation or an anion is known as ionic radius. An ion is formed by either loss or gain of electrons from its valence shell.
- As we move down the group in periodic table the ionic radius increases as the electrons are added to new subshell. As we move across the period the ionic radius increases as the electrons are added to the same subshell.
- An anion is formed when an electron is added to the valence shell of an atom. The anion has a net negative charge in it. In anion the extra electron added occupies more space and maximizes the shielding.
- Anions will have larger size compared to cations.
- The reduction in the effective nuclear charge on the electron cloud, due to a difference in the attraction forces of the electrons in the nucleus is known as shielding effect
- When the proton number is greater than the electron, the size of the ion will be smaller due to less shielding. When the proton number is lesser than the electron, the size of the ion will be larger due to more shielding.
- A cation is formed when an electron is lost by an atom from its valence shell. The cation has a net positive charge. In cation the shielding decreases as the electron is removed from the valence shell.
- If the total number of electrons is less than the total number of protons in the ion, then the protons present can effectively attract the valence shell decreasing the size of the ion and vice-versa.
- The trend in periodic table can be described as well. As we move down the group the ionic radius decreases as the electrons are added to a new shell. But as we move across a period in periodic table the ionic radius increases as the electrons are added to the same subshell.
Answer to Problem 8.43QP
In (b)
Explanation of Solution
The number of electrons and protons in the given set of species (b)
Species | Total number of Electrons | Total number of Protons |
11 | 11 | |
10 | 11 |
The total number of electrons and protons present for the given species are found out and presented in the above table. From this we can see that total numbers of protons in all the given species are same, but the total numbers of electrons are different.
By comparing the total number of protons and electrons in the table given in the previous step it is clear that the number of proton is greater than the electron in
(c)

Interpretation:
In the given set of species which will be smaller in size has to be identified.
Concept Introduction:
- The distance between the nucleus and the valence shell of a cation or an anion is known as ionic radius. An ion is formed by either loss or gain of electrons from its valence shell.
- As we move down the group in periodic table the ionic radius increases as the electrons are added to new subshell. As we move across the period the ionic radius increases as the electrons are added to the same subshell.
- An anion is formed when an electron is added to the valence shell of an atom. The anion has a net negative charge in it. In anion the extra electron added occupies more space and maximizes the shielding.
- Anions will have larger size compared to cations.
- The reduction in the effective nuclear charge on the electron cloud, due to a difference in the attraction forces of the electrons in the nucleus is known as shielding effect
- When the proton number is greater than the electron, the size of the ion will be smaller due to less shielding. When the proton number is lesser than the electron, the size of the ion will be larger due to more shielding.
- A cation is formed when an electron is lost by an atom from its valence shell. The cation has a net positive charge. In cation the shielding decreases as the electron is removed from the valence shell.
- If the total number of electrons is less than the total number of protons in the ion, then the protons present can effectively attract the valence shell decreasing the size of the ion and vice-versa.
- The trend in periodic table can be described as well. As we move down the group the ionic radius decreases as the electrons are added to a new shell. But as we move across a period in periodic table the ionic radius increases as the electrons are added to the same subshell.
Answer to Problem 8.43QP
In (c)
Explanation of Solution
The number of electrons and protons in the given set of species (c)
Species | Total number of Electrons | Total number of Protons |
8 | 10 | |
16 | 18 |
The total number of electrons and protons present for the given species are found out and presented in the above table.
The given two species belong to group “6A” of periodic table. The oxygen atom comes before the sulphur atom when we move down the periodic table. As discussed above, when we move down the group the ionic radius increases because the electrons are added to a new subshell. Hence,
(d)

Interpretation:
In the given set of species which will be smaller in size has to be identified.
Concept Introduction:
- The distance between the nucleus and the valence shell of a cation or an anion is known as ionic radius. An ion is formed by either loss or gain of electrons from its valence shell.
- As we move down the group in periodic table the ionic radius increases as the electrons are added to new subshell. As we move across the period the ionic radius increases as the electrons are added to the same subshell.
- An anion is formed when an electron is added to the valence shell of an atom. The anion has a net negative charge in it. In anion the extra electron added occupies more space and maximizes the shielding.
- Anions will have larger size compared to cations.
- The reduction in the effective nuclear charge on the electron cloud, due to a difference in the attraction forces of the electrons in the nucleus is known as shielding effect
- When the proton number is greater than the electron, the size of the ion will be smaller due to less shielding. When the proton number is lesser than the electron, the size of the ion will be larger due to more shielding.
- A cation is formed when an electron is lost by an atom from its valence shell. The cation has a net positive charge. In cation the shielding decreases as the electron is removed from the valence shell.
- If the total number of electrons is less than the total number of protons in the ion, then the protons present can effectively attract the valence shell decreasing the size of the ion and vice-versa.
- The trend in periodic table can be described as well. As we move down the group the ionic radius decreases as the electrons are added to a new shell. But as we move across a period in periodic table the ionic radius increases as the electrons are added to the same subshell.
Answer to Problem 8.43QP
In (d)
Explanation of Solution
The number of electrons and protons in the given set of species (d)
Species | Total number of Electrons | Total number of Protons |
10 | 12 | |
10 | 13 |
The total number of electrons and protons present for the given species are found out and presented in the above table. From this we can see that total number of electrons in all the given ions is same, but the total numbers of protons are different.
The number of proton in
(e)

Interpretation:
In the given set of species which will be smaller in size has to be identified.
Concept Introduction:
- The distance between the nucleus and the valence shell of a cation or an anion is known as ionic radius. An ion is formed by either loss or gain of electrons from its valence shell.
- As we move down the group in periodic table the ionic radius increases as the electrons are added to new subshell. As we move across the period the ionic radius increases as the electrons are added to the same subshell.
- An anion is formed when an electron is added to the valence shell of an atom. The anion has a net negative charge in it. In anion the extra electron added occupies more space and maximizes the shielding.
- Anions will have larger size compared to cations.
- The reduction in the effective nuclear charge on the electron cloud, due to a difference in the attraction forces of the electrons in the nucleus is known as shielding effect
- When the proton number is greater than the electron, the size of the ion will be smaller due to less shielding. When the proton number is lesser than the electron, the size of the ion will be larger due to more shielding.
- A cation is formed when an electron is lost by an atom from its valence shell. The cation has a net positive charge. In cation the shielding decreases as the electron is removed from the valence shell.
- If the total number of electrons is less than the total number of protons in the ion, then the protons present can effectively attract the valence shell decreasing the size of the ion and vice-versa.
- The trend in periodic table can be described as well. As we move down the group the ionic radius decreases as the electrons are added to a new shell. But as we move across a period in periodic table the ionic radius increases as the electrons are added to the same subshell.
Answer to Problem 8.43QP
In (e)
Explanation of Solution
The number of electrons and protons in the given set of species (e)
Species | Total number of Electrons | Total number of Protons |
79 | 79 | |
76 | 79 |
The total number of electrons and protons present for the given species are found out and presented in the above table. From this we can see that total number of protons in the given species is same, but the total numbers of electrons are different.
By comparing the total number of protons and electrons in the table given in the previous step it is clear that the number of proton is greater than the electron in
Want to see more full solutions like this?
Chapter 8 Solutions
Chemistry
Additional Science Textbook Solutions
General, Organic, and Biological Chemistry - 4th edition
Brock Biology of Microorganisms (15th Edition)
Campbell Essential Biology with Physiology (5th Edition)
Fundamentals Of Thermodynamics
Organic Chemistry
- may you please show all steps! i am having a hard time understanding and applying in this format, thank you!arrow_forward10. Complete the substitution reaction of 2 pentanol with these reagents. Reagents & Reaction Conditions use practice sheet. Please write only major products, minor product like water, other gases are not required. Hint: In substitution of alcohol, we generally substitute OH group with Halogens like cl, Br, F using some reagent containing halogens. Ensure to add halogens to the same carbon number where you are removing OH from Examples Alcohols can be converted to Alkyl Halides with HX acids HBr H₂O HCI + H₂O HI + H₂O CH,CH₂OH + SOCI₂ CH,CH₂OH + PCI₁₂ A BBYJU'S CH CHCI + SO₂+ HCI CH₂CH CIP(OH), + HCI CH,CH₂OH + PCI CHCHCI + POCI + HCI CH,CH₂OH + PBr, CH,CH,Br + P(OH), + HBr 1. Reaction with HBr with 2 Pentanol 2.Reaction with HI with 2 pentanol © Byjus.com 3.Reaction with HCI+ZnCl,, with 2 pentanol (Zncl2 is catalyst no role) 4.Reaction with SOCI,, with 2 Pentanol 5.Reaction with PBr; or PCl, with 2 pentanolarrow_forward3. Is 2-methyl-2-propanol a primary, secondary, or tertiary alcohol? Write out the structures of 2-methyl-2-propanol and also any oxidation products of 2- methyl-2- propanol. If there is more than one oxidation product, give the structure of each of the products. 4. 2-Propanol is the IUPAC systematic name of this alcohol. It has a common name by which it is much better known (You'll see it in the grocery store or pharmacy). Give that common name 5. Aldehydes can be synthesized by the oxidation of. Please choose from below choices A. Primary alcohols B. Secondary alcohols C. Organic acids D. Inorganic acids 6. Tertiary alcohol Can undergo oxidation. yes or no. ? If yes then answer the product.arrow_forward
- Finish the reactions hand written pleasearrow_forwardPart A Identify each alcohol as primary, secondary, or tertiary Drag the appropriate items to their respective bins. CH₂ H₂C- -C-OH HO CH₂ Primary Он OH CH₂ OH CCH₂OH CH₂ сн Secondary Tertiary Reset Help CH,CH₂ (CH)CHCH,OH CH,CH,CH,CCH, CHOH CH₂ Different types of alcohol groups Alcohol and its reaction: 8. Combing two alcohol molecules below and completing the reaction with Product .( Hint Reaction called etherification as ether is formed and name the ether once you complete the reaction. Hint.: R-O-H+H-O-RR-O-R Do the reaction: CH₂OH + CH₂OH---→ + H-O-H 9. Write the reaction of formation of alcohol from alkene by adding water: Addition reaction also called hydration reaction as we are adding water which occur always in presence of acid Hint: Break the double bond and add H and OH if symmetrical then add anywhere if unsymmetrical then follow Markovnikov rule H should go to that double bone carbon which has more hydrogen CH2=CH2 + H₂O-→arrow_forwardComplete the reaction hand written pleasearrow_forward
- Predict the major products of this organic reaction: HBr (1 equiv) cold ? Some important notes: • Draw the major product, or products, of this reaction in the drawing area below. • You can draw the products in any arrangement you like. • Pay careful attention to the reaction conditions, and only include the major products. • Be sure to use wedge and dash bonds when necessary, for example to distinguish between major products that are enantiomers. • Note that there is only 1 equivalent of HBr reactant, so you need not consider the case of multiple additions. dm Re Explanation Check ©2025 McGraw Hill LLC. All Rights Reserved. Termarrow_forwardb) Use curved arrows to show the reaction of the radical with hydrogen bromide. Br: Br H .. Answer Bankarrow_forwardIndicate the reaction products when CH3COCH2COOCH2COOC2H5 (ethyl acetoacetoacetate) reacts with 1º OH-/H2O and 2º H3O+arrow_forward
- Introduction to General, Organic and BiochemistryChemistryISBN:9781285869759Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar TorresPublisher:Cengage LearningChemistry: Principles and ReactionsChemistryISBN:9781305079373Author:William L. Masterton, Cecile N. HurleyPublisher:Cengage Learning

