1. Properties of Materials
National 3 Unit 3 – Chemistry in Society

2. What are Properties?
Properties of materials are things that describe the appearance and characteristics of a material.
Examples of properties are:
Strong
Malleable
Conductivity
Solubility

3. Testing for Conductivity
To test the conductivity of a substance you can place it in an electrical circuit.
If the bulb lights up then the substance must conduct electricity
Battery
Bulb
Substance

4. Testing for Conductivity
Battery
Substance
Bulb
Substance
Conducts (yes/no)
Wood No
Copper Strip
Yes
Plastic
Glass
Iron Nail
In general:
Metals conduct
Non-metals do not conduct

5. Useful Properties
Properties of materials make them suited for their use
Material
Use
Properties
Metal Copper
Electrical Wires
Good conductor of electricity
Plastic
Bottles
Lightweight and water insoluble
Metal Aluminium
Pans
Good conductor of heat and high melting point
Metal Iron
Fences
Strong, malleable and cheap

6. Novel Materials
Scientists have made new materials for special uses. These are known as novel materials.
Material
Properties
Use
Benefit
Kevlar
Lightweight and strong
Bullet proof vests
Keeps policemen safe without having to wear anything too heavy
UV Beads
Sensitive to UV lights
Test sun cream
Ensures sun creams work effectively to reduce skin damage in the sun
Poly(ethanol)
Plastic that is soluble in water
Hospital laundry bags
Prevents nurses touching dirty clothing which reduces a risk of infection

7. National 3 Unit 3 – Chemistry in Society
Chemical Analysis
National 3 Unit 3 – Chemistry in Society

8. Safety in the Lab
When working with chemicals it is important to know the hazards associated with them. Knowing the potential risks allows you to put steps in place to keep yourself as safe as possible.

9. Hazard Symbols
Chemical bottles now have to clearly display special symbols to highlight the hazards associated with them. These symbols are known as Hazard Symbols.

10. Hazard Symbols
Vehicles and containers used to transport chemicals must also display hazard symbols.

11. Chemical Testing in the Environment
It is important to carry out chemical testing in the environment. Scottish Water is a company who carry out various chemical tests to local waters.

12. Chemical Testing of Water
pH Testing
Ion Testing
Test pH of water
Using:
pH indicator
pH paper
pH meter
Different tests to identify the presence of different ions
Ion
Chemical Test
Result
Carbonate
Dilute acid
Fizzing
Sulfate
Barium chloride
White Precipitate formed
Halides
Silver nitrate
Precipitate formed

13. Chemical Testing of Water
When chemical tests are carried out they are always repeated at least 3 times and a mean average is taken from the results
Calculating an average
Add up all the results and divide by the number of repeats
e.g.
Average = 𝟖+𝟗+𝟖+𝟕+𝟖 𝟓
= 𝟒𝟎 𝟓
= 8
Test
pH Measured 1 8 2 9 3 4 7 5