Question
What happens when calcium is treated with water?
  1. It does not react with water.
  2. It reacts violently with water.
  3. It reacts less violently with water.
  4. Bubbles of hydrogen gas formed stick to the surface of calcium.
  1. 1 and 4
  2. 2 and 3
  3. 1 and 2
  4. 3 and 4

Answer

  1. 3 and 4

Explanation: Calcium reacts less violently with water producing the bubbles of hydrogen gas along with calcium hydroxide (Ca(OH)2).

$\text{Ca(s)}+2\text{H}_2\text{O(l)}\rightarrow\text{Ca(OH)}_2\text{(aq) + H}_2\text{(g)}\uparrow$​​​​​​​

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