Question 1
Which of the following reactions are
not consistent with the concept of acid base amphoterism?
◦ Al(OH)
3(
s) ⇌ Al
3+(
aq) + 3 OH
-(
aq)
◦ Al(OH)
3(
s) + OH
-(
aq) → Al(OH)
4-(
aq)
◦ Al(OH)
3(
s) + 3 H
3O
+(
aq) → Al
3+(
aq) + 6 H
2O(
l)
◦ H
2O(
l) + H
2O(
l) ⇌ H
3O
+(
aq) + OH
-(
aq)
Question 2
Barium hydroxide is slightly soluble in water, with a K
sp of 5.00 × 10
-4 at 298K. The dissolution of barium hydroxide in water is an endothermic process.
Ba+2 (aq) + 2OH- (aq)
Which of the following will increase the solubility?
◦ Sodium hydroxide (NaOH) is added to the solution.
◦ Barium hydroxide is added to the solution.
◦ The temperature is decreased.
◦ HCl is added to the mixture. (HCl reacts with OH-, removing it from the system.)