Ncert Exercises & Solutions

Consider the following figures:

a. 16 g of gas

b. 22.4 L of gas

c. $6.022 \times 10^{23}$ dioxygen molecules

d. 11.2 L of gas

Which of the following figures does not represent 1 mole of dioxygen gas at STP?

1. a, b

2. b, c

3. c, d

4. a, d

Hint: At STP, 1 mole of gas is equa to 22.4L

It is known that 1 mole of a gas = gram molecular mass = Avogadro's number of molecules = 22.4 L at STP

Thus, 1 mole of O₂ gas = 32 g of O₂=

6.022 \times 10^{23}

molecules = 22.4 L of O₂ at STP