What is the maximum number of emission l | 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

Ram Herenj
2019-08-02 19:53:56

English me Ansar chahiy uor achi tarah se Ansar Hona chahiy.

Iswarya
2019-07-07 21:18:08

Amazing

Dev
2019-05-28 08:42:47

Good one

Dev
2019-05-28 08:42:26

Nice

Dev
2019-05-28 08:42:00

Nice

Subhangkar mudoi
2018-07-23 19:25:53

How n(n-1)/2

sathvik
2018-07-11 21:21:22

Maximum number of spectral lines possible when an electron jumps from 5th excited state to ground state in a sample containing only one hydrogen atom will be

Rohit singh
2018-02-25 12:49:41

What is the maximum possible number of spectra lines when the hydrogen atom is in its 2nd excited state?

lalnandan
2017-08-31 08:53:11

in a sample one H atom is in first exited state two he+ ion in second excited state and three li2+ions are in third excited state. then,find the maximum number of spectral lines which can be obtained,when all possible transitions terminate at n=1

abhinay
2017-08-07 16:39:01

awesome explanation

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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 15: What is the maximum number of emission lines when the excited electron of an H atom in n = 6 drops t....

What is the maximum number of emission l | Class 11 Chemistry Chapter Structure of Atom, Structure of Atom NCERT Solutions

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