Kinetic theory and gas behaviourIB MYP Sciences: Mind map

Exam questions on Kinetic theory and gas behaviour

1. A hospital stores oxygen gas in sealed steel cylinders in a room with an air-conditioning system. The gas particles inside each cylinder are in constant random motion.
   A cylinder is left in hot sunlight. Explain, in terms of particles, why the pressure of the gas inside it increases.2 marks
2. In a kitchen in Mumbai, the smell of spices frying on the stove reaches the far side of the room within a minute. In the same kitchen, a drop of food colouring added to a glass of water slowly spreads until the whole glass is coloured, without anyone stirring it.
   The cook finds that the smell of the spices spreads more quickly when the kitchen is warm. Explain this using the particle model.2 marks
3. A class investigates how temperature affects diffusion. They add one crystal of potassium manganate(VII) to a beaker containing 200 cm³ of water and time how long it takes for the purple colour to spread evenly through the water. They repeat the test with water at different temperatures.
   State a testable hypothesis for this investigation, including a scientific reason.3 marks