Question

What happens when potassium is added to water?

• A. No reaction
• B. Metal melts and float
• C. Metal is set on fire
• D. Metal move around quickly on water

Answer 1

Answer: (B), (C), (D)

Metal melts and float
Metal move around quickly on water
Metal is set on fire

When potassium is added to water, the metal floats and melts, metal is set on fire and metal moves around quickly on the water.

Potassium reacts with water to form potassium hydroxide and hydrogen gas.

Due to liberation of hydrogen gas, potassium floats and moves around quickly on the water.

Since the reaction of potassium with water is exothermic, the metal melts and is set on fire.

$2K+2H_{2}O\to 2KOH+H_2$

Hence the correct options are B, C, and D.