Tiny smoke particles are suspended in air inside a glass cell. When illuminated and observed through a microscope, they are seen to move.
Describe this movement.
Explain this movement in terms of air molecules and the smoke particles.
A student spills a small amount of propanone (acetone) on their hand. Propanone evaporates very rapidly at room temperature.
State whether the student's hand experiences heating, cooling, or neither at the site where the propanone is spilled. Explain your answer.
State any effect on the rate of evaporation of the propanone if a fan blows air across the student's hand.
321 exam-style questions on CIE IGCSE Physics 2.1 Kinetic particle model of matter, covering 2.1.1 States of matter and changes of state, 2.1.2a Particle structure and motion in solids, liquids and gases, 2.1.2b Gas pressure and particle collisions, 2.1.2c Brownian motion, 2.1.3a The absolute scale of temperature, and 2.1.3b Pressure, volume and temperature of a gas. Each one has a worked solution and a mark scheme showing where the marks go.