Definition of density
How much mass (particles) there are in a given volume (space)
Properties of a gas
.Very weak forces between gas particles as they are far apart
.Can be compressed
.Have no fixed volume or shape
.Low density
.Have the most energy
Apparatus needed to find the density of a regular solid
.Ruler
.Digital balance
.Regular solid to test
Units of mass
kg
Process from a solid to a gas
Sublimation
Process from a gas to a liquid
Condensation
Why is it that solids cannot be compressed easily?
The particles are already packed closely together
Process from a liquid to a solid
Freeze
Method to find the density of an irregular shaped solid
1.Measure the mass of the irregular shaped solid by placing it on the digital balance
2.Place a displacement can on a brick
3.Place the empty beaker under the sprout and fill the can with water. Water should be dripping from the sprout
4.Wait until the water stops dripping from the sprout. Instead, place a measuring cylinder under the sprout
5.Tie the irregularly shaped solid to the string. Very carefully lower the irregularly shaped solid into the displacement can until it’s completely submerged
6.Find the volume of the irregularly shaped solid by finding the volume of water that poured into the measuring cylinder.
7.Find the density of the irregularly shaped solid by knowing that density = mass/volume. Give your answer in the units kg/m³
Method to find the density of a liquid
1.Measure the mass of the empty beaker by placing it on the digital balance
2.Pour a desired volume of liquid inside the measuring cylinder
3.How much has been poured into the measuring cylinder will be the volume of the liquid
4.Pour the liquid inside the beaker
5.Calculate the mass of the liquid (mass of beaker and liquid - mass of empty beaker)
6. Calculate the density of the liquid knowing that density = mass/volume. Give your answer in the units kg/m³
Process from a liquid to a gas
Boil/Evaporation
Units of volume
m³
Give an example of sublimation occurring in a solid
Dry ice
Why do substances change state?
Changes in energy
Method to find the density of a regular solid
- Find the object that is going to be measures
2.Use the ruler to carefully measure the length, width, and height of the object
3.Multiply the numbers together to find the volume of the object
4.Measure the mass of the object by placing it on the digital balance
5.Calculate the density knowing that density = mass/volume. Give your answer in the units kg/m³
Apparatus needed to measure the density of an irregular solid
.Digital balance
.Displacement can and something to stand it on
.Measuring cylinders
.Beaker of water and an extra empty beaker
.Paper towels if water is spilled
.Cotton or thin string
.Irregular shaped solid to test
Why can liquids flow?
Particles move past each other
Process from a solid to a liquid
Melt
Units of density
kg/m³
Apparatus needed to find the density of a liquid
.Digital balance
.Beaker
.Measuring Cylinder
.Liquid to test
Properties of a liquid
.Can flow
.Particles held closely together by strong forces
.Are dense so cannot be compressed easily
.Can change its shape
.Cannot change its volume
Properties of a solid
.Particles held tightly by strong forces
.Particles vibrate around fixed positions
.Have a definite shape and volume
.High density
.Cannot be compressed easily
.Have the least amount of energy
Equation to find density
Þ = m/v
Process from a gas to a solid
Deposition
