Question

Avogrado's Number is the number of molecules present in :

• A. 22.4 litres of a gas at NTP
• B. 1 g-molecule of a substance
• C. 32 g of oxygen
• D. none of the above

Answer 1

Answer: (A), (B), (C)

The correct options are
A 22.4 litres of a gas at NTP
B 1 g-molecule of a substance
C 32 g of oxygen

As we know, one mole of each gas contains $6.023\times {10}^{23}$ molecules and have $22.4$ L volume at standard temperature and pressure.
Also, one mole of gas has gram molar mass, so $32$ g oxygen will have $N_A$ molecules of it.