C2 - Material Choices

Materials & Properties
Some materials are found naturally, wood paper and cotton silk leather, and some are synthetic (man-made) plastic.

Materials have differnt properties, such as: melting point, strenth (tensile - pushing force, and compressive - pushing force), stiffness (how bendy), hardness, and density (density is mass per volume g/cm^3).

The uses for a material depend on its property- ie wood is hard so it can be used for tables, and silk is smooth so can be used for clothes.

The properties of a product depend on what its made from. To assess the suitabilty of different materials, you need to work out what you want it to do, and if the mareials do that. IE: a toy car has to be non-toxic, strong, stiff nd low density, whereas cooking utensils have to have a high melting point, hard, non-toxic, etc.

Crude Oil
Crude oil is a mixture of hydrocarbons- the chains of hydrocarbons are different lengths, as the length changes, the properties of the hydrocarbon change. Shorter changes have a lower melting point.

Crude oil cannot be used straight out of the ground - you have to take it to a refinary so that it can undergo fractional distillation. Different lengths of the hydrocarbons evapourate at different temperatures, and you can use this to seperate the hydrocarbons.…