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

Why are pentahalides more covalent than | Class 12 Chemistry Chapter The p-Block Elements, The p-Block Elements 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

DHARMAPANDIAN
2019-07-22 11:27:21

More the polarization more the covalent. I couldn't understand this line. If there is more polarization it could be more ionic. Am i correct.please clarify me

Vicly
2019-07-04 09:31:40

Supb

Shyam
2019-03-06 19:19:20

Great one.

Yogesh
2019-03-06 12:27:51

Nice ... no words

Abhishek Singh
2019-02-17 15:13:14

Thank a lot

Abhishek Singh
2019-02-17 15:12:41

Thank a lot

Shivam
2019-01-19 14:16:23

your answer gives exact knowledge which not found anywhere .great work!

Lavina
2019-01-12 15:14:33

Really great thanks alot! It clear my alot of doubts

Jazzy Kang
2018-11-13 13:29:06

THANK YOU!!!

Yogesh
2018-11-09 08:06:44

Best answers ever than other books.

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Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 1 , Question 1: Why are pentahalides more covalent than trihalides?....

Why are pentahalides more covalent than | Class 12 Chemistry Chapter The p-Block Elements, The p-Block Elements NCERT Solutions

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