Chapter 2, Problem 10P

(a)

Interpretation Introduction

Interpretation:

The more stable base between $B{r}^{-}$ and $I^{-}$ has to be identified.

Concept introduction:

If a base receives one proton, then the formed species is a conjugate acid whereas an acid lose one proton, then the formed species is a conjugated base.

If an acid lose one proton, then the formed species is a conjugated base. Weak base forms stronger conjugated acid.

Size affecting the stability of the base: In order to determine the strength of the base, the size of an atom overrides electronegativity. As the atoms get larger and the stability of the anions increases even though the electronegativity of the atoms decreases. Stability of the bases increases going down the group. Stable bases are weak bases.

(b)

Interpretation Introduction

Interpretation:

 The more stable base between $C{H}_3{O}^{-}$ and $C{H}_3{S}^{-}$ has to be identified.

Concept introduction:

If a base receives one proton, then the formed species is a conjugate acid whereas an acid lose one proton, then the formed species is a conjugated base.

If an acid lose one proton, then the formed species is a conjugated base. Weak base forms stronger conjugated acid.

Size affecting the stability of the base: In order to determine the strength of the base, the size of an atom overrides electronegativity. As the atoms get larger and the stability of the anions increases even though the electronegativity of the atoms decreases. Stability of the bases increases going down the group. Stable bases are weak bases.

(c)

Interpretation Introduction

Interpretation:

The more stable base between $C{H}_{3}C{H}_2{O}^{-}$  and $C{H}_{3}CO{O}^{-}$ has to be identified.

Concept introduction:

If a base receives one proton, then the formed species is a conjugate acid whereas an acid lose one proton, then the formed species is a conjugated base.

If an acid lose one proton, then the formed species is a conjugated base. Weak base forms stronger conjugated acid.

Electronegativity: The chemical behavior of an atom where it attracts the shared electron pair to itself. Down the group, electronegativity decreases as the number of energy levels increases.

Electronegativity depends on the acidity of a species. Order of electronegativity of hybridization is $sp>s{p}^2>s{p}^3$ so $s{p}^3$ hybridized molecule is weak acid.

Effect of electron delocalization: if a base has localized electrons, then the negative charge that results when the base’s conjugate acid loses a proton will belong to one atom.

A base with delocalized electron is more stable than a similar base with localized electrons.

(d)

Interpretation Introduction

Interpretation:

The more stable base between $H_{2}C=\stackrel{-}{C}H$ and $HC\equiv C^{-}$ has to be identified.

Concept introduction:

If a base receives one proton, then the formed species is a conjugate acid whereas an acid lose one proton, then the formed species is a conjugated base.

If an acid lose one proton, then the formed species is a conjugated base. Weak base forms stronger conjugated acid.

Electronegativity: The chemical behavior of an atom where it attracts the shared electron pair to itself. Down the group, electronegativity decreases as the number of energy levels increases.

Effect of Hybridization: Electronegativity depends on the acidity of a species. Order of electronegativity of hybridization is $sp>s{p}^2>s{p}^3$ so $s{p}^3$ hybridized molecule is weak acid.

(e)

Interpretation Introduction

Interpretation:

The more stable base between $FC{H}_{2}C{H}_{2}CO{O}^{-}$ and $BrC{H}_{2}C{H}_{2}CO{O}^{-}$ has to be identified.

Concept introduction:

If a base receives one proton, then the formed species is a conjugate acid whereas an acid lose one proton, then the formed species is a conjugated base.

If an acid lose one proton, then the formed species is a conjugated base. Weak base forms stronger conjugated acid.

Electronegativity: The chemical behavior of an atom where it attracts the shared electron pair to itself. Down the group, electronegativity decreases as the number of energy levels increases.

Effect of Inductive electron withdrawal on Acidity: Replacing a Hydrogen with an electronegative substituent pulls bonding electrons toward itself; increases the strength of the acid.

(f)

Interpretation Introduction

Interpretation:

The more stable base between $ClC{H}_{2}C{H}_2{O}^{-}$ and $ClCHC{H}_2{O}^{-}$ has to be identified.

Concept introduction:

If a base receives one proton, then the formed species is a conjugate acid whereas an acid lose one proton, then the formed species is a conjugated base.

If an acid lose one proton, then the formed species is a conjugated base. Weak base forms stronger conjugated acid.

Electronegativity: The chemical behavior of an atom where it attracts the shared electron pair to itself. Down the group, electronegativity decreases as the number of energy levels increases.

Effect of Inductive electron withdrawal on Acidity: Replacing a Hydrogen with an electronegative substituent pulls bonding electrons toward itself; increases the strength of the acid.