All matter is either pure or a mixture. Pure matter - elements (atoms) or compounds (molecules)....

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• All matter is either pure or a mixture.

• Pure matter - elements (atoms) or compounds (molecules).

• Mixtures - homogenous (joined) or heterogeneous (separate).

• All atoms present before a chemical reaction must be present after. (Law of Conservation of Matter)

• Chemical formula represents the type and amount of elements that make up the compound – AlCl3

Properties of Materials

• Use the periodic table to differentiate among metals, nonmetals and metalloids

• Classify elements as metals, nonmetals or metalloids based on their propertaies

• Describe different types of physical and chemical properties.

Physical properties Chemical properties

Metalloids Lustre Malleability

Ductility State Hardness

Melting Point Boiling point Viscosity

Density Solubility Combustible

KEY TERMS

Physical properties • Traits that can be observed or measured without

changing the composition of matter.

• Used to observe and describe matter.

Examples of Physical Properties:

1. State – solid, liquid or gas at room temperature.

2. Hardness – how difficult it is to scratch or dent.

3. Melting point – unique temperature needed to change from solid into liquid.

4. Boiling point – unique temperature needed to change from liquid into gas.

5. Lustre – shiny or dull.

6. Malleability – how easy to bend or flatten. (opposite – brittle)

7. Ductility – how easy to pull into a wire.

8. Viscosity – how easy it flows or moves.

9. Solubility – does it dissolve in water.

10. Conductivity – will heat/electricity go through.

11. Density

• A measure of how much matter (stuff) is in a volume of substance.

Water has a density of 1 g/cm3 Lead has a density of 11.34 g/cm3

atoms

Unit of density is grams per cubic centimetre g/cm3 OR g/mL (1 cm3 = 1 mL)

Same size = same volume.

heavier

density = mass

volumedensity = mass volume

Lead Water

If you have 3.0 mL of an element that has a mass of 2.0 grams, what is the density of this element?

d = m v

d 3.0 mL

= 2.0 g

d = 0.67 g/mL

Chemical properties • Describes how a substance will react with another

substance to form new materials.

• Cannot be observed without changing the original material.

Examples:1. Combustion – does it burn or ignite when mixed.

2. Corrosion – does it react with acids.

3. Oxidation – does it react with air.

4. Hydration – does it react with water.

5. Heating – does it react to heat.*Don't confuse with boiling – state change/physical.

Metals • Most common form of matter – 75% of elements.

• Metals demonstrate similar (but NOT identical) physical and chemical properties.

Non-metals• 15% of elements.

• Non-metals demonstrate properties that are the opposite of metals.

Metalloids:• Elements on the staircase – 6% of elements. • Exhibit properties between metal and non-metals.

Property Metal Nonmetal Metalloid

Lustre

Malleable

Ductile

State (Rm Tp)

Conduct heat

Conduct electricity

(*) – there are exceptions to these properties

shiny

solid*

dull shiny*

solid / gas* solid

semi

*

*

*

Zinc:

Copper:

Glycerol:

Water:

d = m v

d = m v

d = m v

d = m v