Acid Base Review

Which of the following is the best definition of an acid?

• An acid is an electron acceptor.

• An acid is a substance that tastes sour.

• An acid is a substance that donates H+.

• An acid is a substance that accepts H+.

The sourness of food is a reasonable guide to its acidity, since sourness increases with increasing acidity. If food A is more sour than food B, then it is likely that:

• A has a higher pH than B

• A has more OH−(aq) ions than B

• B is a stronger acid than A

• A has a higher concentration of H3O+(aq) ions than B.

Hydrogen sulfide, H2S, is a gas at room temperature and dissolves in water. When this solution is tested, it conducts electricity and turns litmus solution red. The solution is acidic because:

• the H2S has gained a proton

• the H2O has gained a proton

• the H2S and H2O have gained protons

• the H2S and H2O have lost protons.

The conjugate base of the species H2PO3 −(aq) is:

• H3PO3(aq)

• HPO4 2−(aq)

• H2PO4(aq)

• HPO3 2−(aq).

Which of the following materials is the most acidic?

• Grapefruit juice of pH 3.0

• Detergent of pH 10.5

• Gastric juice of pH 1.0

• Sea water of pH 8.5

Ammonia solution is alkaline due to the presence of:

• NH4 + ions

• OH− ions

• NH3 molecules

• both NH4 + and OH− ions

The strength of an acid is determined by:

• the number of hydrogen ions present

• its concentration

• its degree of ionisation in aqueous solution

• its ability to change the colour of litmus.

The pH of a solution having an OH- concentration of 0.000 01 M is:

• 5

• 7

• 9

• 14

When dissolved in rain, which of the following gases does not cause it to be acidic?

• O2

• CO2

• NO2

• SO3

A neutralization reaction will (almost) always produce...

• water & salt
• water
• salt
• water & carbon