Which hybrid orbitals are used by carbon | 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

  • Johann
  • 2019-11-16 20:23:47

myself whore sharma like vary nice answer


  • Shivam
  • 2019-07-02 21:09:53

Well explained


  • Shivani
  • 2019-04-24 00:04:12

Very well explained


  • Shivani
  • 2019-04-24 00:03:26

Well explained


  • Satyam kumar gupta
  • 2018-10-20 20:34:43

thnq so much


  • ADARSH KUMAR YADAV
  • 2018-09-26 22:17:36

Thanks


  • Op
  • 2018-09-09 06:11:49

Thanks


Comment(s) on this Question

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 30: Which hybrid orbitals are used by carbon atoms in the following molecules? (a)CH3–CH3; (....