# Worksheet 4B: Gas Laws II

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## Q1

The typical atmospheric pressure on top of Mt. Everest is about 265 torr. Convert this pressure to:

1. atm
2. mmHg
3. Pascals

## Q2

A fixed quantity of gas at 23°C exhibits a pressure of 735 torr and occupies a volume of 5.22 L

1. Calculate the volume the gas will occupy if the pressure is increased to 1.88 atm while temp is held constant.
2. Calculate the volume the gas will occupy if the temperature is increased to 165 °C while the pressure is held constant.

## Q3

Calculate the number of molecules in a deep breath of air whose volume is 2.50L at body temperature, 37°C and a pressure of 735 torr.

## Q4

A scuba diver’s tank contains 0.29 kg of $$O_2$$ compressed into a volume of 2.3 L.

1. Calculate the gas pressure inside the tank at 9°C
2. What volume would this oxygen occupy at 26°C and 0.95 atm?

## Q5

A mixture of $$Ar$$ and $$CO$$ gases is collected over water at 28oC and an atmospheric pressure of 1.05 atm. If the partial pressure of $$Ar$$ is 600 torr, what is the partial pressure of $$CO$$? (vapor pressure of water at 28oC is 28.3 mmHg)

## Q6

Determine the partial pressures of each of the gases in the following mixture: 17.04 g $$NH_3$$, 40.36 g $$Ne$$ and 19.00 g $$F_2$$. The gases are at 1.5 atm of pressure.

## Q7

Potassium chlorate decomposes under heat as follows:

$2KClO_{3\,(s)} \rightarrow 2KCl_{(s)} + 3O_{2\,(g)}$

The oxygen gas is collected over water at 25oC. The volume of gas is 560 mL measured at 1 atm. Calculate the number of grams of $$KClO_3$$ used in the reaction (vapor pressure of water = 0.0313 atm).

## Q10

Drano uses a mixture of sodium hydroxide and aluminum powder to generate hydrogen gas and heat when placed in a drain. Calculate the volume of $$H_2$$ produced at STP if 3.12 g of $$Al$$ is used. (Mole ratio is $$3H_2$$ to $$2Al$$).

## Q12

How many liters of water vapor are generated after 2 L of hydrogen gas react with 1 L of oxygen gas (assuming no changing pressure and temperature)?

$2H_{2(g)} + O_{2(g)} \rightarrow 2H_2O_{(g)}$

## Q13

What is the theoretical volume of air required to completely burning 50 cubic meters of acetylene gas ($$C_2H_2$$) if the air contains 21% of oxygen (assuming no changing pressure and temperature)?

## Q14

In a combustion chamber containing 5 L of carbon monoxide and 2.5 L of oxygen is ignited at 298 K and 1 atmosphere pressure. Assuming complete combustion and no loss of gas, what will be the volume of carbon dioxide formed at 298 K and 1 atmosphere pressure?

## Q15

What volume of propane $$C_3H_{6(g)}$$ reacts with $$100 \;cm^3$$ of oxygen used in the complete combustion reaction, assuming no changing pressure and temperature: (hint: construct the balanced combustion reaction).

$C_3H_{6(g)} + 5O+2 \rightarrow 3CO_2 + 4H-2O$

## Q16

Liquid water can be decomposed into hydrogen and oxygen under suitable conditions (e.g., electrolysis) via the balanced reaction:

$2H_2O_{(l)} \rightarrow 2H_{2(g)} + O_{2(g)}$

If an experiment generates 2500 cm3 of $$H_2$$ gas, what volume of $$O_2$$ is generated under the same conditions of temperature and pressure?

Worksheet 4B: Gas Laws II is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.