Question

A flask contains 0.004 moles of neon gas. calculate the weight in grams [Ne=20]

Answer 1

mass of 1 mole of neon gas = 20g

mass of 0.004 mole of neon gas = 0.004 × 20 = 0.08 gram

Answer 2

Given:

Amount of Neon gas = 0.004 moles

The molecular mass of Ne= 20g

To find:

Weight of gas in grams

Solution:

We know that 1 mole of a substance weighs equal to the gram molecular mass of the substance.

Thus 1 mole of Neon gas weighs 20 g

Using unitary method, mass of 0.004 mole = 20 X 0.004

= 2 X 0.04

= 0.08g

Hence, the weight of gas in the flask is 0.08g.