Homogeneous: the composition of the mixture is uniform throughout. Heterogeneous: composition of the mixture is not uniform. Ex: concrete, milkshake: separation of mixtures, filtration: separate heterogeneous mixtures of liquid/solid, distillation: separates liquids with different boiling points. Physical change: the identity of the matter has not changed. Chemical change: the original substance no longer exists. Extensive properties: value of a substance based on its mass (mass/volume/length) Intensive properties: value of substance does not depend on the amount of matter (density/temperature) Tgm-kdc-m np 12, 9, 6, 3, -1, -2, -3, -6, -9, -12. Exact numbers: numbers with defined values, obtained by counting. Ex: 1 dozen=12 items, there are 12 people in a room. Inexact numbers: numbers found other than counting, such as measuring. Precision: how close a series of replicate measurements are to one another. F = (9 f/5 f)(temp in c) + 32 f. Cathode ray: metal plates connected to high voltage source.