Oxygen is present in a litre flask at a pressure of 76 × 10 - 10 mm of Hg . Calculate the number of oxygen molecules in the flask at 0 ° C .

Given, Pressure, P = 76 × 10 - 10 mm Hg . Temperature, T = 0 ° C = 0 + 273 = 273 K . We know that, P = 7 . 6 × 10 - 10 mm Hg = 7 . 6 × 10 - 10 760 atm = 10 - 12 [ ∵ 1 atm = 760 mm Hg ] . According to the ideal equation, PV = nRT . Where, n = number of moles. R = gas constant, R = 0 . 0821 L atm K - 1 mol - 1 . n = PV RT = 10 - 12 × 1 0 . 0821 × 273 = 4 . 4 × 10 - 14 mol . The number of oxygen molecules, n × N A = 4 . 4 × 10 - 14 × 6 . 023 × 10 23 = 2 . 7 × 10 10 .

E M B I B E

Bureau's Higher Secondary Chemistry Volume-1>Chapter 6 - States of Matter : Gases and Liquids>QUESTIONS>Q 11

EASY

11th Odisha Board

IMPORTANT

Earn 100

A hydrocarbon having the formula $C_{n} H_{2 n + 2}$ diffuses twice as fast as ${SO}_{2}$ at the same temperature. Calculate the value of $n$ .

Important Questions on States of Matter : Gases and Liquids

EASY

11th Odisha Board

IMPORTANT

Bureau's Higher Secondary Chemistry Volume-1>Chapter 6 - States of Matter : Gases and Liquids>QUESTIONS>Q 12

A sample of pure gas at $27 ° C$ and $380 torr$ occupied a volume of $492 {cm}^{3}$ . What was the number of moles of gas in this sample?

EASY

11th Odisha Board

IMPORTANT

Bureau's Higher Secondary Chemistry Volume-1>Chapter 6 - States of Matter : Gases and Liquids>QUESTIONS>Q 13

A desiccator of internal volume of

1

litre and containing nitrogen at one atmospheric pressure is partially evacuated to a final pressure of

7.6 mm

of

Hg

while the temperature remains constant. What is the volume of the gas at this stage?

EASY

11th Odisha Board

IMPORTANT

Bureau's Higher Secondary Chemistry Volume-1>Chapter 6 - States of Matter : Gases and Liquids>QUESTIONS>Q 14

Argon cylinder containing cooking on can withstand a pressure of

14.9

atmosphere. The pressure gauge of the cylinder indicates

12

atmosphere at

27 ° C

. Due to a sudden fire in the building, the temperature starts rising. At what temperature will the cylinder explode?

EASY

11th Odisha Board

IMPORTANT

Bureau's Higher Secondary Chemistry Volume-1>Chapter 6 - States of Matter : Gases and Liquids>QUESTIONS>Q 15

What is the volume of

6 gms

of Hydrogen gas at

1.5 atm

and at

273 ° C

?

EASY

11th Odisha Board

IMPORTANT

Bureau's Higher Secondary Chemistry Volume-1>Chapter 6 - States of Matter : Gases and Liquids>QUESTIONS>Q 16

Calculate the density of

{NH}_{3}

at

30 ° C

and

5 atm

pressure?

EASY

11th Odisha Board

IMPORTANT

Bureau's Higher Secondary Chemistry Volume-1>Chapter 6 - States of Matter : Gases and Liquids>QUESTIONS>Q 17

Calculate the total number of electrons present in

1.6 gms

of methane.

EASY

11th Odisha Board

IMPORTANT

Bureau's Higher Secondary Chemistry Volume-1>Chapter 6 - States of Matter : Gases and Liquids>QUESTIONS>Q 18

An open vessel at

27 ° C

is heated until three fifth of the air in it has been expelled. Assuming that the volume of the vessel remains constant, find the temperature to which the vessel has been heated?

EASY

11th Odisha Board

IMPORTANT

Bureau's Higher Secondary Chemistry Volume-1>Chapter 6 - States of Matter : Gases and Liquids>QUESTIONS>Q 19

Oxygen is present in a litre flask at a pressure of