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

Which one of the following will have lar | 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

Aaliya Bashir
2021-01-13 08:43:05

Very good answer

Mayur Dehankar
2019-12-08 21:05:34

Very properly answered

Shreyas
2019-10-31 14:00:31

Thanksâ¤!

Pratap Dhumal
2019-08-07 19:17:52

I like it very muchð

Ameesha
2019-07-02 20:44:34

Very good answer

Rahul
2019-02-11 21:34:18

Awesome

Jashan
2019-01-30 10:18:07

Thanks

Ambikesh
2018-08-30 13:58:01

Thanks

Harsh
2018-07-06 22:38:39

Correct it is very helpful

Manik Khurana
2018-04-28 12:17:28

Thanks a lot

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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 28: Which one of the following will have largest number of atoms? (i) 1 g Au (s) ....

Which one of the following will have lar | Class 11 Chemistry Chapter Some Basic Concepts of Chemistry, Some Basic Concepts of Chemistry NCERT Solutions

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