Question

How many grams are there in the following :
i) 2 moles of hydrogen molecule H2
ii) 3 moles of chlorine molecule Cl2
iii) 5 moles of sulphur molecule S8
iv) 4 moles of phosphorus molecule P4​

Answer 1

Answer:

Atomic mass of Cl=35.5g

∴ Mass of Cl present= 1×(2×35.5)=71g

(ii) Atomic mass of S=32g

∴ Mass of S present= 2×(8×32)=512g

(iii) Atomic mass of O=16g

∴ Mass of O present= 4×(3×16)=192g

(iv) Atomic mass of N=14g

∴ Mass of N present= 2×(2×14)=56g

Answer 2

Answer:

1. 2 moles of hydrogen molecule H2

=2×(2×1.008)

=4.032 g

2. 3 moles of chlorine molecule cl2

=3×(2×35.5)

=213 g

3. 5 moles of sulphur molecule s8

=5×(8×32)

=1280 g

4. 4 moles of phosphorous molecule p4

=4×(4×31)

=496 g