Calculate the temperature of 4.0 mol of | Class 11 Chemistry Chapter States of Matter, States of Matter 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

  • Khushbu
  • 2019-03-16 19:15:46

Nice and easy solution , thanks


  • Kukkoo
  • 2019-02-03 19:32:55

Tq a lot . It helped me a lot . Upload question from subject chemistry of 2nd puc. Waiting.............


  • Tara
  • 2018-08-22 09:02:03

Its osm tqsm


  • Didikihmar
  • 2017-07-19 20:11:03

Please can you give me further answers???


  • kalpesh mali
  • 2016-07-04 22:24:47

pressure of gas filled in a closed cylinder 273k is 4 atm . calulate the temp of the gas when its pressure is 5 atm pleas send me the ans as soon as posible


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 12: Calculate the temperature of 4.0 mol of a gas occupying 5 dm3 at 3.32 bar. (R = 0.083 bar dm3 K&n....