# Question #0b3dc

##### 1 Answer
Aug 29, 2017

$7.12 \times {10}^{25}$

#### Explanation:

Each water molecule contributes two (2) hydrogen atoms, and each ammonia molecule contributes three (3) hydrogen atoms, so we have a total of:
$2 \times 2.60 \times {10}^{25} + 3 \times 6.40 \times {10}^{24} =$
$5.2 \times {10}^{25} + 19.2 \times {10}^{24} = 5.2 \times {10}^{25} + 1.92 \times {10}^{25} =$
$7.12 \times {10}^{25}$