Science: Gas Laws: Boyles, Charles, and Ideal Gas Worksheet

Question 1

A gas sample has a volume of 4.0 L at a pressure of 1.5 atm. If the temperature stays constant and the pressure increases to 3.0 atm, what is the new volume?

Accepted Answer

Using Boyle's law, P1V1 = P2V2. Substituting values gives (1.5 atm)(4.0 L) = (3.0 atm)(V2). Solving gives V2 = 2.0 L. The new volume is 2.0 L.

Question 2

A balloon has a volume of 2.5 L at 300 K. If the pressure remains constant and the temperature increases to 360 K, what is the new volume?

Accepted Answer

Using Charles's law, V1/T1 = V2/T2. Substituting values gives 2.5 L/300 K = V2/360 K. Solving gives V2 = 3.0 L. The new volume is 3.0 L.

Question 3

A container holds 1.0 mol of gas at 2.0 atm and 273 K. If the container volume is 11.2 L, does this data agree with the ideal gas law? Use R = 0.0821 L-atm/mol-K.

Accepted Answer

Using the ideal gas law, PV = nRT. Calculate nRT = (1.0 mol)(0.0821 L-atm/mol-K)(273 K) = 22.4 L-atm. Calculate PV = (2.0 atm)(11.2 L) = 22.4 L-atm. Since both sides are equal, the data agrees with the ideal gas law.

Question 4

A gas occupies 750 mL at 25 degrees C. If the pressure stays constant and the gas is cooled to 0 degrees C, what is the new volume? Express your answer in milliliters.

Accepted Answer

First convert temperatures to kelvin. The initial temperature is 298 K and the final temperature is 273 K. Using Charles's law, V1/T1 = V2/T2. Substituting values gives 750 mL/298 K = V2/273 K. Solving gives V2 about 687 mL. The new volume is about 687 mL.

Question 5

A syringe contains 30.0 mL of air at 1.00 atm. The plunger is pushed until the volume is 12.0 mL at constant temperature. What is the new pressure?

Accepted Answer

Using Boyle's law, P1V1 = P2V2. Substituting values gives (1.00 atm)(30.0 mL) = (P2)(12.0 mL). Solving gives P2 = 2.50 atm. The new pressure is 2.50 atm.

Question 6

A gas has a volume of 5.00 L, a pressure of 1.20 atm, and a temperature of 350 K. How many moles of gas are present? Use R = 0.0821 L-atm/mol-K.

Accepted Answer

Using the ideal gas law, n = PV/RT. Substitute the values: n = (1.20 atm)(5.00 L) / [(0.0821 L-atm/mol-K)(350 K)]. This gives n about 0.209 mol. There are about 0.209 mol of gas present.

Question 7

A gas sample occupies 9.0 L at 0.80 atm. If the temperature remains constant, what pressure is needed to compress the gas to 6.0 L?

Accepted Answer

Using Boyle's law, P1V1 = P2V2. Substituting values gives (0.80 atm)(9.0 L) = (P2)(6.0 L). Solving gives P2 = 1.2 atm. The required pressure is 1.2 atm.

Question 8

A gas has a volume of 1.80 L at 250 K. At constant pressure, what temperature in kelvin is needed for the volume to increase to 2.16 L?

Accepted Answer

Using Charles's law, V1/T1 = V2/T2. Substituting values gives 1.80 L/250 K = 2.16 L/T2. Solving gives T2 = 300 K. The required temperature is 300 K.

Question 9

What is the pressure of 0.500 mol of a gas in a 10.0 L container at 300 K? Use R = 0.0821 L-atm/mol-K.

Accepted Answer

Using the ideal gas law, P = nRT/V. Substitute the values: P = (0.500 mol)(0.0821 L-atm/mol-K)(300 K) / 10.0 L. This gives P about 1.23 atm. The pressure is about 1.23 atm.

Question 10

Explain in words the main difference between Boyle's law and Charles's law.

Accepted Answer

Boyle's law describes the relationship between pressure and volume when temperature is constant. Charles's law describes the relationship between volume and temperature when pressure is constant.

Question 11

A sealed flask contains gas at 2.0 L, 1.0 atm, and 300 K. If the amount of gas is 0.0812 mol, does this approximately satisfy PV = nRT? Use R = 0.0821 L-atm/mol-K.

Accepted Answer

Calculate PV first: (1.0 atm)(2.0 L) = 2.0 L-atm. Then calculate nRT: (0.0812 mol)(0.0821 L-atm/mol-K)(300 K) about 2.00 L-atm. Since the values are approximately equal, the flask data does satisfy the ideal gas law.

Question 12

A student says gas temperatures can be used in degrees Celsius directly in Charles's law calculations. Is the student correct? Explain.

Accepted Answer

The student is not correct. Charles's law requires absolute temperature, so temperatures must be converted to kelvin before calculating. Using degrees Celsius directly can give incorrect ratios and incorrect answers.

Science: Gas Laws: Boyles, Charles, and Ideal Gas

Science: Gas Laws: Boyles, Charles, and Ideal Gas

More Chemistry Worksheets

More Grade 9-12 Worksheets