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

Find energy of each of the photons which | Class 11 Chemistry Chapter Structure of Atom, Structure of Atom 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

Shamil pp
2019-08-19 21:08:20

You explained very simply...... so this is very usefull.... thank you alðð

Shamil pp
2019-08-19 21:07:43

You explained very simply...... so this is very usefull.... thank you alðð

Shivam rawat
2019-08-03 21:59:36

Thank you

Rajat rana
2019-08-02 12:55:45

Thanks to all

Vishal pal
2019-03-07 10:12:15

Har question ka jawab nahi milta hai

Abhay kumar
2019-01-20 19:58:14

thank you!

satyam
2019-01-16 15:21:35

thanks......bhai

Sneha
2018-09-27 20:26:37

Thanks

Harsh
2018-09-08 16:14:11

Thanks

iba babu
2017-08-16 19:07:03

thanks

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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 6: Find energy of each of the photons which (i) correspond to light of frequency 3× 1015 Hz. ....

Find energy of each of the photons which | Class 11 Chemistry Chapter Structure of Atom, Structure of Atom NCERT Solutions

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