Chapter 13, Problem 35A

Interpretation Introduction

Interpretation: The given pressure is to be calculated in kPa and atm.

Concept introduction:

The force perpendicularly exerted on the surface of an object divided by the region or area over which it is dispersed is known as pressure. The pressure is measured in various units. The units in which pressure is measured are:

• Pascal
• $\text{N}/{\text{m}}^{\text{2}}$
• mmHg
• atm
• Torr

Answer to Problem 35A

  $\text{0}\text{.25 atm}$

  $\text{25}\text{.33 kPa}$

Explanation of Solution

The given pressure is $190\text{ mmHg}$

The relation between atm and mmHg is as shown,

  $1\text{ atm}=760\text{ mmHg}$

Calculate the pressure in atm as follows:

  $\begin{array}{c}190\text{ mmHg}=190\bcancel{\text{mmHg}}\times \frac{1\text{ atm}}{760\bcancel{\text{mmHg}}}\\ =\text{0}\text{.25 atm}\end{array}$

Thus, pressure in atm is $\text{0}\text{.25 atm}$ .

Now, calculate the pressure in kPa as shown:

  $1\text{ atm}=101.325\text{ kPa}$

  $\begin{array}{c}0.25\text{ atm}=0.25\bcancel{\text{atm}}\times \frac{101.325\text{ kPa}}{1\bcancel{\text{atm}}}\\ =\text{25}\text{.33 kPa}\end{array}$

Thus, pressure in kPa is $\text{25}\text{.33 kPa}$ .