The number of oxygen molecules in a cylinder of volume 1 m 3 at a temperature of 27° C and pressure 13.8 Pa is (Boltzmaans constant k=1.38 × 10-23 J K-1 ) is :

Question

The number of oxygen molecules in a cylinder of volume 1 m 3 at a temperature of 27° C and pressure 13.8 Pa is (Boltzmaans constant k=1.38 × 10-23 J K-1 ) is : (A)  6.23× 1026 (B)  0.33× 1028 (C)  3.3× 1021 (D) none of these

Tardigrade Admin · Accepted Answer

Number of molecules of oxygen in the cylinder is n=(P V/R T)=(13.8 × 1/1.38 × 10-23 × 300) =3.3 × 1021

Q. The number of oxygen molecules in a cylinder of volume $1 m^{3}$ at a temperature of $2 7^{\circ} C$ and pressure $13.8 P a$ is (Boltzmaans constant $k = 1.38 \times 1 0^{- 23} J K^{- 1}$ ) is :

$6.23 \times 1 0^{26}$

$0.33 \times 1 0^{28}$

$3.3 \times 1 0^{21}$

none of these

Number of molecules of oxygen in the cylinder is
$n = \frac{P V}{RT} = \frac{13.8 \times 1}{1.38 \times 1 0 ^{- 23} \times 300}$
$= 3.3 \times 1 0^{21}$

Q. The number of oxygen molecules in a cylinder of volume 1m3 at a temperature of 27∘C and pressure 13.8Pa is (Boltzmaans constant k=1.38×10−23JK−1 ) is :

6.23×1026

0.33×1028

3.3×1021