Question

Which of the following statements are true regarding the reaction of metals with water?

• A. All metals react with water.
• B. Magnesium reacts with cold water.
• C. Magnesium reacts with steam.
• D. Potassium reacts with cold water.

Answer 1

Answer: (C), (D)

Potassium reacts with cold water.

$\bullet$ Potassium reacts vigorously with cold water to form potassium hydroxide and hydrogen gas. This can be represented as:

$\text{Potassium}+\text{Water}\to \text{Potassium hydroxide}+\text{Hydrogen gas}$

$\bullet$ Magnesium is less reactive in nature. It does not react with cold water. It reacts with steam to form magnesium hydroxide and hydrogen gas. The reaction involved is:

$\text{Magnesium}+\text{Water}\to \text{Magnesium hydroxide}+\text{Hydrogen gas}$

$\bullet$ All metals do not react with water. For example: noble metals (gold, silver, platinum).