all matter is either pure or a mixture. pure matter - elements (atoms) or compounds (molecules)....
TRANSCRIPT
• 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