Review definitions of molar mass, density and square root determination using a calculator, Define the rate of diffusion of gases as the being inversely proportional to the square root of the molar mass of the gases. Write the formula. Determine that a gas which is 4 times the molar mass of a second gas would diffuse through a pinhole at 1/2 the rate. Use an example of hydrogen gas and oxygen gas in a container. Determine that the hydrogen molecules would diffuse 4X faster than the oxygen molecules.
Begin discussion on chemical and physical changes in matter using Zn and HCl as examples.