# Question #1fb6a

Jun 5, 2017

$164.086 g / m o l$

#### Explanation:

$C a {\left(N {O}_{3}\right)}_{2} \implies C {a}_{\textcolor{red}{1}} {\left({N}_{\textcolor{b l u e}{1}} {O}_{\textcolor{g r e e n}{3}}\right)}_{\textcolor{b r o w n}{2}}$

There are $\left(\textcolor{red}{1} C a\right)$, $\left(\textcolor{b r o w n}{2} \times \textcolor{b l u e}{1} N\right)$, $\left(\textcolor{b r o w n}{2} \times \textcolor{g r e e n}{3} O\right) \implies 1 C a$, $2 N$, $6 O$

Find molar mass of each (coefficient$\times$ atomic mass)

1) $1 C a$: $1 \times 40.078 = 40.078 g / m o l$

2) $2 N$: $2 \times 14.007 = 28.014 g / m o l$

3) $6 O$: $6 \times 15.999 = 95.994 g / m o l$

Add all these masses to get the molar mass of $C a {\left(N {O}_{3}\right)}_{2}$

$40.078 + 28.014 + 95.994 = 164.086 g / m o l$