IB Chemistry SL/HL — Paper 1 (S1.5: Ideal Gases)

Which of the following assumptions is part of the kinetic molecular theory of gases?

• Gas particles have strong intermolecular forces.

• The volume of gas particles is significant compared to the container.

• Collisions between gas particles are elastic.

• Gas particles move slowly at all temperatures.

At constant temperature, the volume of a fixed mass of gas is inversely proportional to its pressure. This statement represents:

• Boyle’s law

• Charles’s law

• Avogadro’s law

• Dalton’s law

Which gas law shows that volume is directly proportional to temperature (in kelvin) at constant pressure?

• Boyle’s law

• Charles’s law

• Avogadro’s law

• Ideal gas law

The temperature of a gas doubles while its pressure is kept constant. The volume will:

• A. Double

• B. Halve

• C. Stay the same

• D. Increase four times

Which of the following expressions represents the ideal gas equation?

• PV = nR/T

• PV = RT/n

• PV = nRT

• PV/T = nR²

A gas occupies 2.00 dm³ at 100 kPa. What will be its volume at 200 kPa, assuming constant temperature?

• 1.00 dm³

• 4.00 dm³

• 0.50 dm³

• 2.00 dm³

If 1.00 mol of an ideal gas occupies 24.0 dm³ at 298 K, what is the pressure? (Use R = 8.31 J mol⁻¹ K⁻¹)

• A. 103 kPa

• B. 101 kPa

• C. 82 kPa

• D. 124 kPa

At STP, one mole of gas occupies:

• 22.4 dm³

• 24.0 dm³

• 1.00 dm³

• 20.0 dm³

What does the area under a Maxwell–Boltzmann curve represent?

• Total energy of the gas

• Number of gas particles

• Average kinetic energy

• Pressure of the gas

When temperature increases, the Maxwell–Boltzmann distribution curve:

• Shifts right and flattens

• Becomes steeper

• Moves left

• Remains the same shape