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Calculate the molecular mass of the following: (i) H2O (ii) CO2 (ii...

Calculate the mass of sodium acetate (CH | Class 11 Chemistry Chapter Some Basic Concepts of Chemistry, Some Basic Concepts of Chemistry 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

Ridham Patel
2020-05-29 18:45:51

Thank you

Tanu
2020-05-24 19:30:46

Thanks a lot

Adi
2019-07-21 07:53:18

Thanks for elaboration

Indranil
2019-07-09 15:09:38

Thanks

Saumya
2019-07-07 13:21:56

thanks for such good explanation

Prasoon
2019-06-30 14:40:45

Supriti try to love

ravi
2019-06-23 13:44:59

thnx

ravi
2019-06-23 13:44:11

thanx

Sahil
2019-06-18 17:24:38

Why we multi. 82.0245 with 0.1875 not divede

sakshi
2019-06-05 09:25:20

Thank you but I want it a little more briefly

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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 5: Calculate the mass of sodium acetate (CH3COONa) required to make 500 mL of 0.375 molar aqueous solut....

Calculate the mass of sodium acetate (CH | Class 11 Chemistry Chapter Some Basic Concepts of Chemistry, Some Basic Concepts of Chemistry NCERT Solutions

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