What is the significance of leaching in | Class 12 Chemistry Chapter General Principles and Processes of Isolation of Elements, General Principles and Processes of Isolation of Elements 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

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  • 2020-08-20 03:41:58

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  • 2019-12-17 18:34:00

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  • 2019-10-12 21:32:45

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  • 2019-10-09 14:08:55

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  • 2019-08-27 20:36:50

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  • 2019-06-14 11:30:17

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  • Tejas
  • 2019-02-18 20:19:39

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  • Kuldeep singh
  • 2019-02-18 05:21:31

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  • Md Ashraf
  • 2018-11-21 13:36:26

Thanks.I am satisfied.


  • Piyush
  • 2018-09-17 23:56:21

Very nice


Comment(s) on this Question

Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 1 , Question 2: What is the significance of leaching in the extraction of aluminium?....