1. Characteristic Physical Properties

2. Characteristic Physical Properties
1. Freezing & Melting Point
The Freezing Point is the temperature at which a substance turns from a liquid into a solid
Example: Pure water freezes into ice at 0o Celsius
The Melting Point is the temperature at which the substance turns from a solid into a liquidliquid
Example: Pure ice begins to melt 0o Celsius
The freezing point is the same temperature as the melting point of the same substance!

3. Characteristic Physical Properties
2. Boiling Point
The Boiling Point is the temperature at which a substance changes from a liquid to a gas
Example: Water boils at 100o Celsius
3. Density
Each substance has its own density and can be identified by it …
Let’s take a closer look at this one!

4. What is Density?
a measure of how closely packed the particles are in a substance
the amount of matter a substance has in a certain space (how much mass is contained per unit of volume of a substance)
The units of density are usually g/cm3 for a solid and g/ml for a liquid
A substance with a low density feels “light” and will float in a substance with a higher density.
A substance with a high density feels “heavy” and will sink in a substance with a lower density.

5. Densities of Some Substances
In this picture:
What is the most dense substance?
What is the least dense substance?
What 2 substances have really close densities?

6. Density as an Equation Density (D) = Mass (m) Volume (V)
The equation can be rearranged to suit what you are
trying to find!

7. Solving Equations Use GRASS method:
G-given (state what you are given in the question)
R-required (state what you are trying to find)
A-analyse (write the equation and sub numbers in)
S-solve (calculate your answer)
S-statement (write out your answer in a full sentence)
Must use this method for full marks!!!!

8. Therefore, the density of the material is 3.89 g/cm3.
Calculate the density of a material that has a mass of g and a volume of 13.5 cm3.
D = ?
m = g
V = 13.5 cm3
D = m V
= g
13.5 cm3
= g/cm3
Therefore, the density of the material is 3.89 g/cm3.

9. The density of silver is 10. 49 g/cm3
The density of silver is g/cm3. If a sample of pure silver has a volume of cm3, what would be the mass?
m = ?
D = g/cm3
V = cm3
m = D x V
= x
= g
Therefore, the mass of the sample would be g

10. Therefore, the volume of gold would be 16.51cm3
Pure gold has a density of g/cm3. How large would a piece of gold be if it has a mass of g?
V = ?
D = g/cm3
m = g
V = m D =
19.32
= cm3
Therefore, the volume of gold would be 16.51cm3

11. Practice Problems Answer: 0.47 g/cm3 Answer: 19.23 cm3 Answer: 16.8 g
1) What is the density of a substance with a volume of 30 cm3 and a mass of 14 g?
Answer: 0.47 g/cm3
2) What is the volume of a substance with a density of g/cm3 and a mass of 15 g?
Answer: cm3
3) What is the mass of a substance with a density of g/cm3 and a volume of 15 mL?
Answer: 16.8 g