Question

Calcium hydride reacts with water to form calcium hydroxide (aqueous) and hydrogen gas. Write a balanced chemical equation for the reaction. Express your answer as a balanced chemical equation. Identify all of the phases in your answer.

Answer 1

Answer:

$CaH_2(s) +2H_2O(l) \rightarrow Ca(OH)_2 (aq) + 2H_2 (g)$

Explanation:

$CaH_2(s) +H_2O(l) \rightarrow Ca(OH)_2 (aq) + H_2 (g)$

In this reaction, calcium is balanced in either side. No. of atoms of 'H' and 'O' are not balanced. To balance O atoms, multiply $H_2O$ by 2. Now the reaction becomes:

$CaH_2(s) +2H_2O(l) \rightarrow Ca(OH)_2 (aq) + H_2 (g)$

Now, to balance H atoms, multiply H2 by 2.

$CaH_2(s) +2H_2O(l) \rightarrow Ca(OH)_2 (aq) + 2H_2 (g)$

Now, each element is balanced.