The amount of matter (mass) in a given space (volume) Density The amount of matter (mass) in a given space (volume)

I Density Solving for Density Density = mass divided by volume D = m/V Practice: If you have a glass of water with a mass of 500g (minus the glass), and the volume amounts to 500mL, what is the density of water? 500g/500mL = 1g/mL I Density Volume

Density is a useful physical property for identifying substances, because each substance has a unique density. The density of a substance is always the same at a given temperature and pressure.

Solids in Liquids A solid floats when it is less dense than the liquid that its in, and sinks when it is more dense. So wood is less dense than water and a rock is more dense. Ice will suspend in water, most of its mass will be below water, and (about 8%) will be above the water. This is because its density (.92 g/cm3) is very close the density of liquid water (1.0 g/mL)

Water is the only non-metallic substance on Earth whose density in solid form (ice) is less than its density in liquid form. Why? Liquid water is most dense (1.00 g/mL) as a liquid and becomes less dense as the water molecules form crystals of ice as the temperature drops to 0 °C. This is due to hydrogen bonds forming between the water molecules, which line up molecules less efficiently (in terms of volume) when water is frozen. Hydrogen bonds are weak, constantly forming and breaking to create partially ordered structures in liquid water; in ice, each water molecule bonds rigidly to four others.

Density of Fluids A fluid is any material, liquid or gas, that can flow. Fluid density units are g/ml or kg/L When different fluids combine, the densest fluids form layers on the bottom, less dense layers form at the top.

Density Calculation Practice What is the density of an object whose mass is 23.5 g and whose volume is 10 cm3? D = m/V D = 23.5g/10cm3 D = 2.35 g/cm3 Does the object float?