Let’s Get Physical

Physical Properties A physical property is a characteristic of a material that can be measured or observed but does not change the composition of the material Common physical properties are Viscosity Conductivity Malleability Hardness Melting Point Boiling Point Density

Viscosity Viscosity is a liquids tendency to keep from flowing, its resistance to flow If a liquid is highly viscous this means it does not flow easily Ex. Karo syrup and honey If a liquid has a low viscosity then it flows easily Ex. Water, alcohol, vinegar The colder the temp the higher the viscosity, the higher the temp the lower the viscosity

Conductivity Conductivity is a material’s ability to allow heat to flow through it Most metals have a high conductivity Most materials that are good conductors of heat are also good conductors of electricity Wood is a poor conductor

Most metals are malleable Malleability Malleability is the ability to be hammered into a sheet without shattering Ex. Tin foil Most metals are malleable Ice and class are not malleable because they shatter, instead they are said to be brittle

Hardness and Density When 2 materials are put together, the harder material will always scratch the softer material Diamond is the hardest known material Density is a ratio of mass to volume Density can be used to determine the identity of an unknown material Density can also be used to determine the purity of a known material (gold, silver, copper, ect.)

Melting Point and Boiling Point MP is the temp at which a material goes from a solid to a liquid BP is the temp at which a material goes from a liquid to a gas For water MP is 0°C and BP is 100 °C BP and MP can be useful in determining the identity of an unknown material

Filtration and Distillation Filtration is the process that separates particles based on size Ex. Strainers, coffee filters Distillation is a process that separates materials based on BP Distillation is used in the production of moonshine

Physical Change vs. Chemical Change A physical change occurs when a physical property is changed but not the composition of the material Most physical changes are reversible When chemical changes occurs the composition of the material must change, meaning that a new chemical has been formed