Chapter 10, Problem 99A

Interpretation Introduction

Interpretation: The relation between the given two statements needs to be explained.

Concept Introduction: The relation between pressure, volume, number of moles, and volume of gas is represented by the below equation:

  $PV=nRT$

The conditions at STP are 1 atm pressure and 273.15 K temperature. Since the value of the Universal gas constant is $0.082\text{ L atm/K mol}$ , the volume of 1 mol of the gas will be 22.4 L.

Explanation of Solution

The given two statements are as follows:

1. One mole of any gas at STP has a 22.4 L volume of that gas.
2. There are different atomic volumes and diameters of different elements.

When 1 mol of any gas is considered, the number of atoms in 1 mol will be the same for all the gases that are $6.022\times {10}^{23}$ . For different elements, atomic volumes and diameters are different but when 1 mol of a substance is considered at STP the volume is 22.4 L only. This difference is due to the arrangement of atoms of elements at STP. Since the number of gaseous molecules is the same in 1 mol thus, they arrange in such a way that the molar volume will be 22.4 L irrespective of the individual atomic volumes of the elements present in the gaseous molecules.

Therefore, different bonding and arrangement of atoms in gaseous molecules give the same molar volume for all the gases at STP.