8.1 Brønsted-lowry acids and bases  (Page 4/14)

Write equations that show NH ₃ as both a conjugate acid and a conjugate base.

Write equations that show ${\text{H}}_2{\text{PO}}_4{}^{\text{−}}$ acting both as an acid and as a base.

Show by suitable net ionic equations that each of the following species can act as a Brønsted-Lowry acid:

(a) ${\text{H}}_3{\text{O}}^{\text{+}}$

(b) HCl

(c) NH ₃

(d) CH ₃ CO ₂ H

(e) ${\text{NH}}_4{}^{\text{+}}$

(f) ${\text{HSO}}_4{}^{\text{−}}$

Show by suitable net ionic equations that each of the following species can act as a Brønsted-Lowry acid:

(a) HNO ₃

(b) ${\text{PH}}_4{}^{\text{+}}$

(c) H ₂ S

(d) CH ₃ CH ₂ COOH

(e) ${\text{H}}_2{\text{PO}}_4{}^{\text{−}}$

(f) HS ⁻

Show by suitable net ionic equations that each of the following species can act as a Brønsted-Lowry base:

(a) H ₂ O

(b) OH ⁻

(c) NH ₃

(d) CN ⁻

(e) S ²⁻

(f) ${\text{H}}_2{\text{PO}}_4{}^{\text{−}}$

Show by suitable net ionic equations that each of the following species can act as a Brønsted-Lowry base:

(a) HS ⁻

(b) ${\text{PO}}_4{}^{\text{3−}}$

(c) ${\text{NH}}_2{}^{\text{−}}$

(d) C ₂ H ₅ OH

(e) O ²⁻

(f) ${\text{H}}_2{\text{PO}}_4{}^{\text{−}}$

What is the conjugate acid of each of the following? What is the conjugate base of each?

(a) OH ⁻

(b) H ₂ O

(c) ${\text{HCO}}_3{}^{\text{−}}$

(d) NH ₃

(e) ${\text{HSO}}_4{}^{\text{−}}$

(f) H ₂ O ₂

(g) HS ⁻

(h) ${\text{H}}_5{\text{N}}_2{}^{\text{+}}$

What is the conjugate acid of each of the following? What is the conjugate base of each?

(a) H ₂ S

(b) ${\text{H}}_2{\text{PO}}_4{}^{\text{−}}$

(c) PH ₃

(d) HS ⁻

(e) ${\text{HSO}}_3{}^{\text{−}}$

(f) ${\text{H}}_3{\text{O}}_2{}^{\text{+}}$

(g) H ₄ N ₂

(h) CH ₃ OH

Identify and label the Brønsted-Lowry acid, its conjugate base, the Brønsted-Lowry base, and its conjugate acid in each of the following equations:

(a) ${\text{HNO}}_3+{\text{H}}_2\text{O}⟶{\text{H}}_3{\text{O}}^{\text{+}}+{\text{NO}}_3{}^{\text{−}}$

(b) ${\text{CN}}^{\text{−}}+{\text{H}}_2\text{O}⟶\text{HCN}+{\text{OH}}^{\text{−}}$

(c) ${\text{H}}_2{\text{SO}}_4+{\text{Cl}}^{\text{−}}⟶\text{HCl}+{\text{HSO}}_4{}^{\text{−}}$

(d) ${\text{HSO}}_4{}^{\text{−}}+{\text{OH}}^{\text{−}}⟶{\text{SO}}_4{}^{\text{2−}}+{\text{H}}_2\text{O}$

(e) ${\text{O}}^{\mathrm{2-}}+{\text{H}}_2\text{O}⟶2{\mathrm{OH}}^{\text{−}}$

(f) ${[\text{Cu}{({\text{H}}_2\text{O})}_3(\text{OH})]}^{\text{+}}+{[\text{Al}{({\text{H}}_2\text{O})}_6]}^{\mathrm{3+}}⟶{[\text{Cu}{({\text{H}}_2\text{O})}_4]}^{\mathrm{2+}}+{[\text{Al}{({\text{H}}_2\text{O})}_5(\text{OH})]}^{\mathrm{2+}}$

(g) ${\text{H}}_2\text{S}+{\text{NH}}_2{}^{\text{−}}⟶{\text{HS}}^{\text{−}}+{\text{NH}}_3$

Identify and label the Brønsted-Lowry acid, its conjugate base, the Brønsted-Lowry base, and its conjugate acid in each of the following equations:

(a) ${\text{NO}}_2{}^{\text{−}}+{\text{H}}_2\text{O}⟶{\text{HNO}}_2+{\text{OH}}^{\text{−}}$

(b) $\text{HBr}+{\text{H}}_2\text{O}⟶{\text{H}}_3{\text{O}}^{\text{+}}+{\text{Br}}^{\text{−}}$

(c) ${\text{HS}}^{\text{−}}+{\text{H}}_2\text{O}⟶{\text{H}}_2\text{S}+{\text{OH}}^{\text{−}}$

(d) ${\text{H}}_2{\text{PO}}_4{}^{\text{−}}+{\text{OH}}^{\text{−}}⟶{\text{HPO}}_4{}^{\text{2−}}+{\text{H}}_2\text{O}$

(e) ${\text{H}}_2{\text{PO}}_4{}^{\text{−}}+\text{HCl}⟶{\text{H}}_3{\text{PO}}_4+{\text{Cl}}^{\text{−}}$

(f) ${[\text{Fe}{({\text{H}}_2\text{O})}_5(\text{OH})]}^{\mathrm{2+}}+{[\text{Al}{({\text{H}}_2\text{O})}_6]}^{\mathrm{3+}}⟶{\text{[Fe}{({\text{H}}_2\text{O})}_6]}^{\mathrm{3+}}+{[\text{Al}{({\text{H}}_2\text{O})}_5(\text{OH})]}^{\mathrm{2+}}$

(g) ${\text{CH}}_3\text{OH}+{\text{H}}^{\text{−}}⟶{\text{CH}}_3{\text{O}}^{\text{−}}+{\text{H}}_2$

What are amphiprotic species? Illustrate with suitable equations.

State which of the following species are amphiprotic and write chemical equations illustrating the amphiprotic character of these species:

(a) H ₂ O

(b) ${\text{H}}_2{\text{PO}}_4{}^{\text{−}}$

(c) S ²⁻

(d) ${\text{CO}}_3{}^{\text{2−}}$

(e) ${\text{HSO}}_4{}^{\text{−}}$

State which of the following species are amphiprotic and write chemical equations illustrating the amphiprotic character of these species.

(a) NH ₃

(b) ${\text{HPO}}_4{}^{\text{−}}$

(c) Br ⁻

(d) ${\text{NH}}_4{}^{\text{+}}$

(e) ${\text{ASO}}_4{}^{\text{3−}}$

Is the self ionization of water endothermic or exothermic? The ionization constant for water ( K _w ) is 2.9 $\times$ 10 ⁻¹⁴ at 40 °C and 9.3 $\times$ 10 ⁻¹⁴ at 60 °C.