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Calculate the molecular mass of the following: (i) H2O (ii) CO2 (ii...

Pressure is determined as force per unit | Class 11 Chemistry Chapter Some Basic Concepts of Chemistry, Some Basic Concepts of Chemistry NCERT Solutions

Question:

Calculate the molecular mass of the following:
(i) H₂O
(ii) CO₂
(iii) CH₄

Answer:

Molecules are made up of atoms & are quite small, therefore the actual mass of a molecule cannot be detrmined.It is expressed as the relative mass.C-12 isotope is used to express the relative molecular masses of substances.Thus molecular mass of a substance may be defined as: the average relative mass of its molecule as compared to the mass of carbon atom taken as 12 amu.

(i) H₂O:

The molecular mass of water, H₂O

= (2 × Atomic mass of hydrogen) + (1 × Atomic mass of oxygen)

= [2(1.0084) + 1(16.00 u)]

= 2.016 u + 16.00 u

= 18.016

= 18.02 u

(ii) CO₂:

The molecular mass of carbon dioxide, CO₂

= (1 × Atomic mass of carbon) + (2 × Atomic mass of oxygen)

= [1(12.011 u) + 2 (16.00 u)]

= 12.011 u + 32.00 u

= 44.01 u

(iii) CH₄:

The molecular mass of methane, CH₄

= (1 × Atomic mass of carbon) + (4 × Atomic mass of hydrogen)

= [1(12.011 u) + 4 (1.008 u)]

= 12.011 u + 4.032 u

= 16.043 u

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Comments

Awesome OR
2019-09-17 20:35:55

quite tough to understand but still *GOOD*

Devil
2019-08-14 20:19:14

It is the worst answer

Student
2019-07-26 13:37:45

The method of explaining was inappropriate

Isha
2019-07-17 18:54:28

9.8m^2 kiska value hai ?

Ad
2019-07-15 17:55:22

Yess

Khushi kumari Singh
2019-07-14 15:38:09

9.8m/s kaise aaya A= acceleration so how to used this value

Swalin
2019-07-06 00:23:29

You are a salal Singh Gobber Raj understand

Tushar Singh
2019-07-02 06:51:30

9.8m/s where are you puting

Alphonse
2019-06-05 15:16:21

Rubbish

Kankana Das
2019-05-02 11:24:27

It was quite difficult in understanding

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Welcome to the NCERT Solutions for Class 11 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 1 , Question 13: Pressure is determined as force per unit area of the surface. The SI unit of pressure, Pascal is as ....

Pressure is determined as force per unit | Class 11 Chemistry Chapter Some Basic Concepts of Chemistry, Some Basic Concepts of Chemistry NCERT Solutions

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