Conversions in Chemistry.?

Question

1. A radio station announcer reports the atmospheric pressure to be 99.6 kPa. What is the pressure in atmospheres? In millimeters of mercury?

2. The pressure reading from a barometer is 742 mm Hg. Express this reading in kilopascals, kPa.

3. Analysis of an air sample reveals that it contains 3.5 x 10^-6 psi of carbon monoxide. Express the concentration of carbon monoxide in torr.

4. The pressure reading from a barometer is 540 mm Hg. Express this reading in atmosphere.

5. A balloon has a pressure of 15 atmospheres. Calculate the amount of pressure in mm Hg.

6. Convert 620 atm to Pascal.

7. The pressure reading from a barometer is 567 Pa. Calculate its pressure in mm Hg.

8. A 150 kPa is enclosing in a container. Express its pressure in torr.

9. A SCUBA tank is filled with air at 16.7 atm at 24°C. Calculate the pressure in mm Hg.

10. A tank of gas has a pressure of 20 atm. When you applied force, the half of its original pressure reduces. What will be its new pressure in torr? Calculate the final pressure in mm Hg.

**i have already computed for some. of the questions but i'm not sure. please help me. i need the solutions and answers. thank you very much. :)

Answer 1

let's do the first one:

Here are the conversion factors:

1 atm = 760 mmHg = 101.3 kPa

The first question asks for the pressure to be given in atmospheres. Since there's 101.3 kPa in 1 atm, we convert the given as follows:

99.6 kPa * 1 atm / 101.3 kPa = 0.983 atm

When you convert using dimensional analysis, the unwanted units should cancel out. Put the known unit on top and the unknown at the bottom.

Recall that 1 atm = 760 mmHg and 1 atm = 101.3 kPa

First we have to convert from kPa to atm. Then we convert from atm to mmHg.

99.6 kPa * 1 atm / 101.3 kPa * 760 mmHg / 1 atm = 747 mmHg

:)