Which of the following compounds dissolves in water to give an alkaline solution?
- Ammonium chloride
- Sodium chloride
- Sulphur (IV) oxide
-
Potassium oxide
The correct answer is: D
Explanation
When potassium oxide (K2O) reacts with water (H2O), it produces potassium hydroxide (KOH):
- Chemical equation:
K2O + H2O → 2KOH - The reaction produces a hydroxide compound because the potassium ion balances the hydroxide ion and the solution is alkaline because of the high level of hydroxide ions, which gives it a high pH. Therefore, the correct answer is option D