Class 11 Exam  >  Class 11 Questions  >  The vapour densities of two gases are in the ... Start Learning for Free
The vapour densities of two gases are in the ratio of 1:3.their molecular masses are in the ratio of?
Most Upvoted Answer
The vapour densities of two gases are in the ratio of 1:3.their molecu...
The ratio of the vapour densities of two gases is equal to the ratio of their molecular masses. In order to understand why this is the case, let's delve into the concept of vapour density and molecular mass.

Vapour Density
Vapour density is defined as the ratio of the density of a gas to the density of hydrogen gas under the same conditions of temperature and pressure. It is denoted by the symbol "D" and is a dimensionless quantity.

Molecular Mass
Molecular mass refers to the mass of a molecule, which is the sum of the masses of all the atoms present in the molecule. It is usually expressed in atomic mass units (amu) or grams per mole (g/mol).

Relationship between Vapour Density and Molecular Mass
The relationship between vapour density and molecular mass can be understood by considering the ideal gas equation:
PV = nRT

Where:
P = Pressure
V = Volume
n = Number of moles
R = Gas constant
T = Temperature

By rearranging the equation, we get:
n = (PV) / (RT)

We can rewrite the equation as follows:
n = (m/M) / (RT/V)

Where:
m = Mass of the gas
M = Molecular mass
RT/V = Density of the gas

From this equation, it can be observed that the number of moles (n) of a gas is directly proportional to the ratio of mass (m) to the molecular mass (M) of the gas.

Explanation of the Given Ratio
Given that the ratio of the vapour densities of the two gases is 1:3, we can write it as:
D₁ / D₂ = 1 / 3

Using the relationship between vapour density and molecular mass, we can write:
M₁ / M₂ = D₁ / D₂

Substituting the given ratio of vapour densities:
M₁ / M₂ = 1 / 3

Therefore, the molecular masses of the two gases are in the ratio of 1:3.

Conclusion
The ratio of vapour densities of two gases is equal to the ratio of their molecular masses. This relationship can be derived from the ideal gas equation. In the given scenario, the ratio of the vapour densities is 1:3, which implies that the molecular masses of the gases are also in the ratio of 1:3.
Community Answer
The vapour densities of two gases are in the ratio of 1:3.their molecu...
It's same 1:3
Attention Class 11 Students!
To make sure you are not studying endlessly, EduRev has designed Class 11 study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in Class 11.
Explore Courses for Class 11 exam

Top Courses for Class 11

The vapour densities of two gases are in the ratio of 1:3.their molecular masses are in the ratio of?
Question Description
The vapour densities of two gases are in the ratio of 1:3.their molecular masses are in the ratio of? for Class 11 2024 is part of Class 11 preparation. The Question and answers have been prepared according to the Class 11 exam syllabus. Information about The vapour densities of two gases are in the ratio of 1:3.their molecular masses are in the ratio of? covers all topics & solutions for Class 11 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The vapour densities of two gases are in the ratio of 1:3.their molecular masses are in the ratio of?.
Solutions for The vapour densities of two gases are in the ratio of 1:3.their molecular masses are in the ratio of? in English & in Hindi are available as part of our courses for Class 11. Download more important topics, notes, lectures and mock test series for Class 11 Exam by signing up for free.
Here you can find the meaning of The vapour densities of two gases are in the ratio of 1:3.their molecular masses are in the ratio of? defined & explained in the simplest way possible. Besides giving the explanation of The vapour densities of two gases are in the ratio of 1:3.their molecular masses are in the ratio of?, a detailed solution for The vapour densities of two gases are in the ratio of 1:3.their molecular masses are in the ratio of? has been provided alongside types of The vapour densities of two gases are in the ratio of 1:3.their molecular masses are in the ratio of? theory, EduRev gives you an ample number of questions to practice The vapour densities of two gases are in the ratio of 1:3.their molecular masses are in the ratio of? tests, examples and also practice Class 11 tests.
Explore Courses for Class 11 exam

Top Courses for Class 11

Explore Courses
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev