Question 18M.2.SL.TZ1.2
| Date | May 2018 | Marks available | [Maximum mark: 7] | Reference code | 18M.2.SL.TZ1.2 |
| Level | SL | Paper | 2 | Time zone | TZ1 |
| Command term | Calculate, Explain | Question number | 2 | Adapted from | N/A |
A closed box of fixed volume 0.15 m3 contains 3.0 mol of an ideal monatomic gas. The temperature of the gas is 290 K.
Calculate the pressure of the gas.
[1]
«»
48 «kPa»
[1 mark]
When the gas is supplied with 0.86 kJ of energy, its temperature increases by 23 K. The specific heat capacity of the gas is 3.1 kJ kg–1 K–1.
Calculate, in kg, the mass of the gas.
[1]
mass = «» 0.012 «kg»
Award [1] for a bald correct answer.
[1 mark]
Calculate the average kinetic energy of the particles of the gas.
[1]
1.38 × 10–23 × 313 = 6.5 × 10–21 «J»
[1 mark]
Calculate the average kinetic energy of the particles of the gas.
[1]
1.38 × 10–23 × 313 = 6.5 × 10–21 «J»
[1 mark]
Explain, with reference to the kinetic model of an ideal gas, how an increase in temperature of the gas leads to an increase in pressure.
[3]
larger temperature implies larger (average) speed/larger (average) KE of molecules/particles/atoms
increased force/momentum transferred to walls (per collision) / more frequent collisions with walls
increased force leads to increased pressure because P = F/A (as area remains constant)
Ignore any mention of PV = nRT.
[3 marks]
