Answer
$Mg(OH)_2(aq) + 2HNO_3(aq) --> Mg(NO_3)_2(aq) + 2H_2O(l) $
Work Step by Step
1. Write the unbalanced equation:
$Mg(OH)_2(aq) + HNO_3(aq) --> Mg(NO_3)_2(aq) + H_2O(l) $
2. Balance the equation:
*Since there are 2 OH- in $Mg(OH)_2$, the coefficient of $HNO_3$ is going to be 2.
$Mg(OH)_2(aq) + 2 HNO_3(aq) --> Mg(NO_3)_2(aq) + H_2O(l) $
*Since there are 2 OH- reacting with 2H+, we know that it will produce 2 $H_2O$ molecules.
$Mg(OH)_2(aq) + 2HNO_3(aq) --> Mg(NO_3)_2(aq) + 2H_2O(l) $
