Chemistry Quiz on Acid-Base Concepts

Conjugate acid-base pair of a substance differ in terms of

• number of hydrogen atoms

• charge carried by them

• ionizable hydrogen atoms

• hydrogen ion and hydroxyl ion

The conjugate base of NH4+ is

• N2H2

• NH2

• NH2OH

• NH3

The following equilibrium exists in aqueous solution CH3COOH ⇌ H+ + CH3COO- when dil. HCl is added,

• the equilibrium constant will increase

• acetate ion concentration increases

• acetate ion concentration decreases

• the equilibrium constant will decrease

Calculate the concentration of H+ ions in 0.1 M HCOOH solution. (Ka of formic acid= 1.8 x 10-5)

• 1.8 x 10-4

• 1.8 x 10-6

• 1.3 x 10-2

• 1.3 x 10-3

According to Lewis concept, a reaction between an acid and base is the transfer of

• proton from acid to base

• OH- ion from base to acid

• electron pair from base to acid

• electron pair from acid to base

Strength of a base depends on

• concentration of water.

• concentration of base

• number of OH group present in the base molecule.

• number of hydroxyl ions, it can produce during ionization

Sea water has a pH of 8.2. The concentration of hydrogen ion [H+] in various salts is

• 6.3 X 10-8 M.

• 6.3 X 10-9 M.

• 6.3 X 10-7 M.

• 6.3 X 10-6 M.

What is the pH of a solution with a hydroxide ion concentration [OH-] of 1 x 10-8 M?

• 6

• 7

• 8

• 14

A 0.0516M solution of HNO3 has a pH of 2.34. what is the Ka?

NH3 (g) + H2O ⇌ NH4+(aq) + OH-(aq)

• the acid in above reaction is NH3

• The acid in above reaction is H2O

• The acid is NH4

• The acid is OH-