Question

1. How many molecules of S2 gas are in 756.2 L?

Answer 1

Answer: There are $2.032 \times 10^{25}$ molecules $S_{2}$ gas are in 756.2 L.

Explanation:

It is known that 1 mole of any gas equals 22.4 L at STP. Hence, number of  moles present in 756.2 L are calculated as follows.

$Mole = \frac{Volume}{22.4 L}\\= \frac{756.2 L}{22.4 L}\\= 33.76 mol$

According to mole concept, 1 mole of every substance contains $6.022 \times 10^{23}$ molecules.

Therefore, molecules of S present in 33.76 moles are calculated as follows.

$1 mol = 6.022 \times 10^{23}\\33.76 mol = 33.76 \times 6.022 \times 10^{23}\\= 2.032 \times 10^{25}$

Thus, we can conclude that there are $2.032 \times 10^{25}$ molecules $S_{2}$ gas are in 756.2 L.