EASY
9th CBSE
IMPORTANT
Earn 100

How many atoms of calcium are present in 2g of calcium? (Atomic mass of Ca=40)

Important Questions on Atoms and Molecules

EASY
9th CBSE
IMPORTANT
Modern's abc+ of SCIENCE CHEMISTRY FOR Class IX>Chapter 3 - Atoms and Molecules>Revision Exercise>Q 25
What is the molar mass of sulphur molecule S8?
MEDIUM
9th CBSE
IMPORTANT
Modern's abc+ of SCIENCE CHEMISTRY FOR Class IX>Chapter 3 - Atoms and Molecules>Revision Exercise>Q 1

State the following law. 

Law of conservation of mass.

MEDIUM
9th CBSE
IMPORTANT
Modern's abc+ of SCIENCE CHEMISTRY FOR Class IX>Chapter 3 - Atoms and Molecules>Revision Exercise>Q 1

State the following law. 

Law of constant proportions.

MEDIUM
9th CBSE
IMPORTANT
Modern's abc+ of SCIENCE CHEMISTRY FOR Class IX>Chapter 3 - Atoms and Molecules>Revision Exercise>Q 2
What is mole? How is it related to molar mass?
 
MEDIUM
9th CBSE
IMPORTANT
Modern's abc+ of SCIENCE CHEMISTRY FOR Class IX>Chapter 3 - Atoms and Molecules>Revision Exercise>Q 3

Correct the following symbols and formulae of elements and compounds.

Lead: PB; Mercury: Me;

Water: H2O2; Ammonia: HN3

MEDIUM
9th CBSE
IMPORTANT
Modern's abc+ of SCIENCE CHEMISTRY FOR Class IX>Chapter 3 - Atoms and Molecules>Revision Exercise>Q 4
Define: Gram atomic mass
MEDIUM
9th CBSE
IMPORTANT
Modern's abc+ of SCIENCE CHEMISTRY FOR Class IX>Chapter 3 - Atoms and Molecules>Revision Exercise>Q 4
Define: Gram molecular mass
HARD
9th CBSE
IMPORTANT
Modern's abc+ of SCIENCE CHEMISTRY FOR Class IX>Chapter 3 - Atoms and Molecules>Revision Exercise>Q 5
Calculate the number of aluminium ions in 0.056 g of aluminium oxide Al2O3.