11. The volume of air in a car tyre is about 1.50 x 102 m3 at a temperature of 0.0C and pressure 250kPa. a) Calculate the number of molecules in the tyre. b) Explain why, after the car is driven for a while, the pressure of the air in the tyre will increase. c) Calculate the new pressure of the tyre when the temperature increases to 35C and the volume expands to 1.60 x 10'2 m3. (1) The car is parked for the night and the volume, pressure and temperature of the air in the tyre return to their initial values. A small leak in the tyre reduces the pressure from 250kPa to 230kPa in the course of 8 h. Estimate (stating any assumptions you make): i) the average rate of loss of molecules (in molecules per second) ii) the total mass of air lost (take the molar mass of air to be 29ng1'1 )