Question

Which of the following has maximum number of molecules ?
a. 7 g N2
b. 2 g H2
c. 8 g O2
d. 20 g NO2

Answer 1

Answer:

2 g H2 has maximum number of molecules

Explanation:

7 g N2 =7 NA /14 (NA =6.022 ×10^23)

=NA /2

2g H2 =NA

8 g O2=NA/2

20g NO2 =20 NA/46

Answer 2

The following has the maximum number of molecules:

(b) 2 g H2

- The no of moles in 7 g of N2 = 7/28 = 0.25 moles

- The no of moles in 2 g of H2 = 2/2 = 1 moles

- The no of moles in 8 g of O2 = 8/32 = 0.25 moles

- The no of moles in 20 g of NO2 = 20/46 = 0.435 moles

- Therefore, 2 g H2 will have the maximum no of molecules as it contains the maximum no of moles.