Describe the hybridisation in case of PC | Class 11 Chemistry Chapter Chemical Bonding and Molecular Structure, Chemical Bonding and Molecular Structure 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

  • Gandheswari
  • 2019-09-24 09:13:20

Thanku


  • haha
  • 2019-09-13 22:38:55

wrong config given... please correct


  • Prakash Pramanik
  • 2018-11-24 21:02:15

Orbital diagram of P atom


  • Prakash Pramanik
  • 2018-11-24 21:01:13

Formation of PCl5 molecule class11th


  • Vijay Hemanth
  • 2018-09-21 11:36:15

Define BMO and ABMO? How is it used to calculate bond order of the molecule???


  • Adarsh Kumar singh
  • 2018-04-20 17:43:06

Answer is right but electronic configuration is wrong because 3P have 3 degerated orbital and 3D have 5.


  • Bijay
  • 2017-10-20 18:26:02

Answer is good but it electroni configuration is give wrong


  • pankaj Sharma
  • 2017-10-12 21:40:59

Nice working with this answered


  • BHAVEY
  • 2016-03-10 18:30:20

exelent...


Comment(s) on this Question

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 38: Describe the hybridisation in case of PCl5. Why are the axial bonds longer as compared to equatorial....