Chemistry Class 11 NCERT Solutions: Chapter 1 Some Basic Concepts of Chemistry Part 1 (For CBSE, ICSE, IAS, NET, NRA 2023)

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Q: 1 Calculate the molecular mass of the following:

Example of Molecular Mass for Carbon Dioxide


Molecular Atomic Mass of 2 Hydrogen + 1 Oxygen


Molecular Atomic Mass of 1 Carbon + 2 Oxygen


Molecular Atomic Mass of 1 Carbon + 4 Hydrogen



The molecular mass of water,


The molecular mass of carbon dioxide,


The molecular mass of methane,


Q: 2 calculate the mass percent of different elements present in sodium sulphate

Na2SO4 is a Typical Ionic Sulfate, Containing Na + Ions and S …
This Structure is Sodium Hydroxide & Copper Sulfate & Solid …


The molecular formula of sodium sulphate is

Molar mass of

Mass percent of an element

∴ Mass percent of sodium:

Mass percent of sulphur:

Mass percent of oxygen: