Introduction of terms Density Preview Introduction of terms Density

A. Terms Observation – interaction with the environment - use your 5 senses Inference – a guess based on observations Law of uniformitarianism – the present is the key to the past

Prediction – a guess (inference) about the future Cyclic – occurs in a pattern, over and over - easy to predict - example: phases of the moon Non-cyclic – occurs randomly - difficult to predict - example: earthquake

B. Density Density is a physical property can be used to identify a substance does not change if material is broken into pieces Density = mass / volume Most objects are most dense as a solid Water is the exception Water expands when it freezes Solid water – ICE - floats Water is most dense (1 g/mL) as a liquid at 3.98°C

Temperature Pressure As temperature increases, density decreases Warm air rises because it is less dense Pressure As pressure increases, density increases