What is the covalence of nitrogen in N2O | Class 12 Chemistry Chapter The p-Block Elements, The p-Block 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

  • Sarkar
  • 2021-02-13 21:36:24

Can't you give the solutions also so that we can cross check...


  • Bolem saikumar
  • 2020-03-27 08:55:31

Good


  • Santhwana
  • 2019-11-10 09:56:15

Thanks


  • Arsh khan
  • 2019-10-11 19:50:30

Thanks sir g ..it is helpful


  • Meghan
  • 2019-08-24 09:49:36

Thanks


  • Pankaj
  • 2019-04-04 12:46:16

Shukriya!kirak jawab


  • Harsh
  • 2019-03-09 19:54:20

Thanks sir ,your questions are really helpful


  • Sachin chavan
  • 2019-02-27 00:01:49

Tanaku..sir


  • Swara
  • 2018-12-19 19:14:21

Thanks I like it.


  • gaurav kumar pandey
  • 2018-06-27 20:22:58

thanks


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 6: What is the covalence of nitrogen in N2O5?....