Question EXE.2.SL.TZ0.7
| Date | Example questions Example questions | Marks available | [Maximum mark: 7] | Reference code | EXE.2.SL.TZ0.7 |
| Level | SL | Paper | 2 | Time zone | TZ0 |
| Command term | Calculate, Discuss, State | Question number | 7 | Adapted from | N/A |
State two assumptions of the kinetic model of an ideal gas that refer to intermolecular collisions.
[2]
The collisions are elastic ✓
The time for a collision is much shorter than the time between collisions ✓
The intermolecular forces are only present during collisions ✓
Discuss how the motion of the molecules of a gas gives rise to pressure in the gas.
[3]
The momentum of a molecule changes when it collides with a container wall ✓
From and Newton’s third law, this leads to a force exerted on the wall by the molecule ✓
The average force exerted by all the molecules on a unit area of the wall is equivalent to pressure ✓
The average speed of the molecules of a gas is 500 m s−1. The density of the gas is 1.2 kg m−3. Calculate, in kPa, the pressure of the gas.
[2]
✓
100 «kPa» ✓