Answer
$Sr(OH)_2 + 2 HNO_3 --> Sr(NO_3)_2 + 2 H_2O$
Work Step by Step
1. Write the unbalanced equation:
$Sr(OH)_2 + HNO_3 --> Sr(NO_3)_2 + H_2O$
2. Balance the equation:
* We will need to add a 2 next to $HNO_3$, because 1 $Sr(NO_3)_2$ has 2 $NO_3$.
$Sr(OH)_2 + 2 HNO_3 --> Sr(NO_3)_2 + H_2O$
*Now, we can analize that, there are 2 $H^+$ reacting with 2 $OH^-$, which will form 2 water molecules$(H_2O)$.
$Sr(OH)_2 + 2 HNO_3 --> Sr(NO_3)_2 + 2 H_2O$
*Now the equation is totally balanced.
