Free Printable IONIC EQUILIBRIA 1

1.

HCO₃^- ion acts as Bronsted-Lowry acid in the reaction

a)

$HCO_3^-(aq)+H_3O^+(aq)\rightarrow2H_2O(l)+CO\ _2$

b)

$HCO_{3^-}(aq)+H_2O(l)→H_2CO_3(aq)+OH^-(aq)$

c)

$HCO_3^-(aq)+OH^-(aq)→H_2O(l)+CO_3^{2^-}\left(aq\right)$

d)

$HCO_3^-(aq)+HSO_4^-(aq)→H_2CO_3(aq)+SO_{4^2}-\left(aq)\right)$

2.

The pH value of a solution of NaOH 2.50x10^-3 M is

a)

2.60

b)

4.50

c)

11.40

d)

12.30

3.

Calculate the concentration of hydroxide ions in an aqueous solution containing 4.0x10^-8 M hydronium ions.

a)

4.0x10^-22

b)

2.5x10^-7

c)

1.0x10^-12

d)

4.0x10^-8

4.

The K_b values of the following bases are

C₆H₇O₆^- K_b = 1.3x10^-10

C₂H₅NH₂ K_b = 5.6x10^-4

C₅H₅N K_b = 1.7x10^-9

Choose the arrangement of the conjugate acids of the above bases in order of increasing acidity.

a)

C₆H₇O₆H < C₅H₅NH⁺ < C₂H₅NH₃⁺

b)

C₅H₅NH⁺< C₂H₅NH₃⁺ < C₆H₇O₆H

c)

C₆H₇O₆H < C₂H₅NH₃⁺ < C₅H₅NH⁺

d)

C₂H₅NH₃⁺ < C₅H₅NH⁺< C₆H₇O₆H

5.

The following solutions are buffer solutions EXCEPT

a)

NH₃ and NH₄Cl

b)

HC₂H₃O₂ and NH₄C₂H₃O₂

c)

HC₂H₃O₂ and NaC₂H₃O₂

d)

NH₃ and (NH₄)₂SO₄

6.

pH of a solution comprising of benzoic acid, C₆H₅COOH 0.25 M and sodium benzoate, C₆H₅COONa 0.15 M is

[K_a C₆H₅COOH = 6.5x10^-5]

a)

3.40

b)

3.97

c)

4.41

d)

4.83

7.

Which of the following salts forms an aqueous solution with the lowest pH value?

a)

NH₄NO₃

b)

Ca(NO₃)₂

c)

KNO₃

d)

Mg(NO₃)₂

8.

For a titration between sulphuric acid and an aqueous solution of ammonia, the most suitable indicator (with its pH range) is

a)

ethyl red (4.5-6.5)

b)

phenol red (6.7-8.5)

c)

phenolphthalein (8.3-10.0)

d)

alizarin yellow (10.1-12.0)

9.

1. Choose the TRUE statement(s) by referring to the ionisation constants for several bases given.

Base K_b

p 4.3x10^-3

q 4.1x10^-5

r 6.7x10^-4

a)

p is the strongest base

b)

q has the highest pK_b value

c)

p, q and r have pH > 9.5

10.

Salt(s) that produce(s) acidic aqueous solution(s) is (are)

a)

$Na_2SO_4$

b)

$Na_4NO_3$

c)

$NaH_2PO_4$

11.

Which graph shows how pH changes when weak base added to strong acid?

a)

A

b)

B

c)

C

d)

D

12.

Which acid base pair produce the titration curve shown below?

a)

HCI + KOH

b)

HCI + NH₃

c)

CH₃COOH + KOH

d)

CH₃COOH + NH₃

13.

What is the volume of weak base 0.1M NH₄OH needed to neutralize 25 ml 0.1M weak acid?

a)

12.5 ml

b)

25 ml

c)

50 ml

d)

more than 25 ml

14.

What are the products of the neutralization shown below?
Ca(OH)₂ + H₂CO₃ -->

a)

H₂O + Ca₂CO₃

b)

CaO + CO₃

c)

H₂O + CaCO₃

15.

Why is indicator added to a titration?

a)

To test for acids

b)

to show the endpoint

c)

to prove a reaction has happened

d)

to show a colour

IONIC EQUILIBRIA 1

Total questions: 15

Worksheet time: 19mins

Similar Resources on Wayground