Chapter U3, Problem SIII1RE

Interpretation Introduction

Interpretation: The number of molecules in a breath of air needs to be determined.

Concept introduction: If two gases have same temperature, pressure and volume then the gases have same number of gas particles independent of the identity of the gas.

Answer to Problem SIII1RE

The number of molecules in a breath of air is $1.25\times {10}^{22}$ .

Explanation of Solution

Avogadro’s number is $6.023\times {10}^{23}$ . At STP volume of 1 mole of gas is $24\times {10}^{-3}{\text{m}}^3$ s. Arrive at an estimate for number of molecules in a single breath is $1.25\times {10}^{22}$ molecules.

Conclusion

Ideal gas equation is as follows:

PV = nRT

Here, P is pressure, V is volume, n is number of mole, R is gas constant and T is temperature.