Neon gas is generally used in the sign b | 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

Rahmat Fatima
2020-07-14 19:29:34

Thqs for this answers

Ankita
2019-07-21 10:25:21

Thank you to SÂ²

Ishita
2019-07-01 20:32:11

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Ritik
2019-06-29 10:41:43

Velocity of radiation ko velocity of light kyo liya

Rana
2019-06-28 18:16:02

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Jenish
2019-06-18 22:00:27

Can you explain option (d) in detail

Kusum
2019-06-09 22:14:15

Nice

Joy
2019-06-07 12:34:39

Thanks

Jot
2019-06-07 12:34:23

Thanks

Manvir singh
2019-05-04 17:49:39

Frequency ma 10 ki power 16 kase ayi

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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 47: Neon gas is generally used in the sign boards. If it emits strongly at 616 nm, calculate (a) the ....

Neon gas is generally used in the sign b | Class 11 Chemistry Chapter Structure of Atom, Structure of Atom NCERT Solutions

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