Question

1 mole of ammonia is of 17 g. Then what is the mass of 0.3 moles of ammonia?

(a) 21g

(b) 2.1g

(c) 17g

(d) 1g

I had been asked this question during a job interview.

Asked question is from Mole Concept and Molar Masses topic in chapter Chemistry Basic Concepts of Chemistry – Class 11

Answer 1

The correct answer is (b) 2.1g

For explanation I would say: Given that, 1 mole of ammonia is of 17 g. 0.3 mole of ammonia contains 17 x 0.3g of mass. IT’s because the molecular weight of a given pcompound is directly proportional to the number of moles of the given compound.