How do you explain the functionality of | Class 12 Chemistry Chapter Polymers, Polymers 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


Study Tips for Answering NCERT Questions:

NCERT questions are designed to test your understanding of the concepts and theories discussed in the chapter. Here are some tips to help you answer NCERT questions effectively:

  • Read the question carefully and focus on the core concept being asked.
  • Reference examples and data from the chapter when answering questions about Polymers.
  • Review previous year question papers to get an idea of how such questions may be framed in exams.
  • Practice answering questions within the time limit to improve your speed and accuracy.
  • Discuss your answers with your teachers or peers to get feedback and improve your understanding.

Comments

  • Manya jain
  • 2019-11-26 14:03:26

Thanku it is very useful for me


  • Yashraj kher
  • 2019-10-17 11:44:12

Very useful for me Thank you very much


  • Aditya pawar
  • 2019-09-07 16:41:58

Thanks it is very very useful for me


  • Isha
  • 2019-03-08 14:35:25

Hyy Listen


  • Sk
  • 2018-04-14 13:25:49

How for propene is one


  • Mohd Modassirul Haque
  • 2018-02-21 15:04:46

For styrene


  • Alien
  • 2017-10-14 19:20:00

Noice


  • Suraj
  • 2017-09-17 13:32:38

For styrene


  • Harsha
  • 2017-04-09 20:21:58

Hi


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Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 2 , Question 4: How do you explain the functionality of a monomer?....