Chapter 9, Problem 12QAP

Interpretation Introduction

Interpretation:

The barometric pressure at the sea level is 760mmHg. The pressure of the pressure cooker is 1.75 atm. The normal boiling point temperature difference between the boiling water in an open pot and in pressure cooker is to be determined. The heat of vaporization of water is ΔH_vap =40.7kJ/mol.

Concept introduction:

The Clausius − Clapeyron equation is as follows:

$\ln \frac{P_1}{P_2}=-\frac{\Delta H_{vap}}{R}\left(\frac{1}{T_1}-\frac{1}{T_2}\right)$

Here,

P₁ and P₂ = vapor pressure

T₁ and T₂ = Temperature

R = gas constant

ΔH_vap = heat of vaporization

The boiling point temperature difference is -

$\Delta T_b=T_2-T_1$