HARD
Diploma
IMPORTANT
Earn 100

Deduce the two acids and their conjugate bases in the following reaction:

H2O(l)+NH3(aq)OH(aq)+NH4+(aq)

Important Questions on Acids and Bases (AHL)

MEDIUM
Diploma
IMPORTANT

Explain why the following reaction can also be described as an acid–base reaction.

F(g)+BF3(g)BF4(s)

HARD
Diploma
IMPORTANT
Define a Lewis acid and state an example that is not a Brønsted–Lowry acid
MEDIUM
Diploma
IMPORTANT
Draw structural formulas to represent the reaction between a Lewis acid and a Lewis base and identify the nature of the bond formed in the product.
HARD
Diploma
IMPORTANT

When these 1.0 mol dm3 acidic solutions are arranged in order of increasing strength (weakest first), what is the correct order?

Acid in solution X : Ka=1.74×105 mol dm3 at  298 K 

Acid in solution Y : Ka=1.38×103 mol dm3 at 298 K 

Acid in solution Z : Ka=1.78×105 mol dm3 at 298K

HARD
Diploma
IMPORTANT
pKw for water at 10C=14.54. What is the pH of pure water at this temperature?
HARD
Diploma
IMPORTANT
What is Kb for the aqueous fluoride ion given that Kw is 1.0×1014 and Ka for HF is 6.8×104 at 298 K?
HARD
Diploma
IMPORTANT
Ammonia acts as a weak base when it reacts with water. What is the Kb expression for this reaction?
HARD
Diploma
IMPORTANT

Ammonia, NH3 , is a weak base. It has a pKb value of 4.75.

Calculate the pH of a 1.00×102 mol dm3 aqueous solution of ammonia at 298 K.