Question

$Mg+H_{2}O\to A+H_2$

$A+H_{2}O\to B$

Identify A and B.

• A. $A\to MgO$ $B\to Mg\left(OH\right)$
• B. $A\to Mg(OH{)}_2$ $B\to MgO$
• C. $A\to MgO$ $B\to Mg(OH{)}_2$
• D. $A\to Mg(OH{)}_2$ $B\to Mg{O}_2$

Answer 1

The correct option is C

$A\to MgO$

$B\to Mg(OH{)}_2$

We know that when metals react with water hydrogen gas is liberated along with the formation of metal hydroxide. The reaction takes place in two steps.

$Mg+H_{2}O\to MgO+H_2$

$MgO+H_{2}O\to Mg(OH{)}_2$

$A\to MgO$

$B\to Mg(OH{)}_2$