Changes in matter

• physical change involves change in state, size, shape, or physical appearance, e.g. melting, evaporation, condensation
• chemical change results in the formation of a new substance where chemical reaction takes place
• diffusion is to spread quickly, movement of a substance from an area of higher concentration to an area of lower
• brownian motion - random motion of particles suspended in a liquid or gas caused by collisions with molecules of the surrounding medium
• exothermic reaction - chemical reaction that releases heat to the surroundings
• endothermic reaction - chemical reaction that absorbs heat from its surroundings