Question

The mass of a carbon atom is 1.994 × 10-23 grams. The mass of a hydrogen atom is 1.67 × 10-24 grams. What is the difference of their masses?
0.324 × 10-24 grams
1.827 × 10-23 grams
1.827 × 10-24 grams
0.324 × 10-23 grams

Answer 1

 1.994 x 10^-23
-0.167 x 10^-23
 1.827 x 10^-23
Correct answer is the second one.