Question

The mass of a hydrogen atom is

1.67 × 10 grams.
-24
The mass of a nitrogen atom is
2.32 × 107 grams.
- 23
A molecule of ammonia contains 3 atoms of
hydrogen and 1 atom of nitrogen.
a) Calculate the mass of one molecule of
ammonia
Give your answer in standard form.
b) Calculate the number of molecules in 1
gram of ammonia.
Give your answer in standard form to 3
significant figures.

Answer 1

(Part a) I plugged in the numbers and got the answer to 3.984 x 10 to the power of 11 grams (assuming hydrogen atomic mass is the first given number and nitrogen is second), which in standard form would be 3.984 * 10^11 grams)

(for part b), I plugged in the numbers again and got 2.496 * 10^23(in standard form it would be 2.496 * 10^23)

Hope it helps?