1 By: Jennings Bryson, Suzanne Hodges & Kyle Oldham The Art of MixturesBy: Jennings Bryson, Suzanne Hodges & Kyle Oldham
2 What Makes Paint a Mixture Paints are a type of mixture called a colloid.Paint contains several components, including the pigment, a solvent, a binding medium, and additives.
3 Paint Ingredients Pigment - gives the paint its color Binding medium - a liquid polymer that hardens to form a continuous layer when the paint driesSolvent - dissolves the binding medium and makes the paint more fluid.(polymer: a large molecule)Additives- small amounts of substances modifying the paint properties
4 Physical ChangeEmulsion paints are water-based. Their solvent is water, and it dries when the water evaporates.Physical change
5 Chemical ChangeThe pigments in oil paints are dispersed in oil, which may itself be dissolved in a solvent.The solvent evaporates away when the paint dries. This leaves the pigment and oil behind. The oil oxidises to form a hard film.This happens because the oil reacts with oxygen in the air.Chemical change
6 Chemical or PhysicalIs mixing two different colors of paint a chemical or physical change?It is a physical change because mixing the two paints does not make a different substance, it simply makes a different color.
7 Oil Paint FactsMost oil paints are undercoats or primers that will always come in a metal canThe paint itself is flammable because it contains petroleum distillates(paint thinner)The vapor it gives off, volatile organic compounds, VOCs, can be very dangerous.
8 Oil Paint facts cont. Extra fact: Before 1978, many paints’ pigments contained so much mercury, that the neurotoxins were harmful to developing children, the adult brain, nervous system, and virtually every organ.Now, the danger of the mercury or VOCs subside after the paint dries.