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

Explain the formation of H2 molecule on | Class 11 Chemistry Chapter Chemical Bonding and Molecular Structure, Chemical Bonding and Molecular Structure 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

imdad
2019-11-13 23:07:57

Thank you so much ð

Sejal
2019-09-09 21:27:36

It's very helpful and explanable one also ...thanks

Shiv Nandan Kumar Rana
2019-08-02 20:40:39

Ncert ka copy paste kar k hero banta hai, lollðððððððð

Baiju kumar jha
2019-02-21 19:20:15

Helpful answer

Aniruddh Jat
2018-12-17 18:58:09

Bhadiya

Himani
2018-11-29 19:06:55

Thanks

Divya
2018-08-26 18:10:37

Best answer

Zohaib
2018-07-15 13:55:42

Professional work !!

Shivee jaiswal
2018-06-23 14:00:01

Superb answer ððððð

Prabhjot singh
2018-04-03 19:33:42

Brilliant answer

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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 33: Explain the formation of H2 molecule on the basis of valence bond theory.....

Explain the formation of H2 molecule on | Class 11 Chemistry Chapter Chemical Bonding and Molecular Structure, Chemical Bonding and Molecular Structure NCERT Solutions

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