Topic: Chemistry
Aim: How can we separate mixtures?
Do Now: Let’s review yesterday’s ISN.
HW: Phases of Matter Reading Notes due
Monday
Phase changes reading notes due Tuesday
1. An element consists of only one type of atom.
2. He atoms have 2 protons and Na atoms have
11 protons.
3. A compound consists of 2 or more
DIFFERENT elements chemically bonded
together.
4. A compound can be broken down.
5. A molecule consists of 2 or more atoms of the
same element or different elements chemically
bonded together.
6. Some molecules are not compounds when
they consist of only a single element.
H2
O2
N2
Molecules
H2O
CO2
CH4
Compounds
These are not compounds because
each is made up of only one element.
These are compounds because each
is made up of 2 or more different
elements.
Are these compounds also molecules?
When atoms
of the same
element join
together we
get a
molecule of
that element.
Oxygen (O2)
Hydrogen (H2)
Compounds will
always exist as
molecules, not
separate atoms.
3 water (H2O) molecules
2 carbon dioxide (CO2)
molecules
Evaporation:
separates solute
from a solvent
Sieve: separates
gravel (small
pebbles) from sand
Filtration: separates
dirt or sand from
water
Chromatography:
separates pigments
in a mixture
Magnet: Separates
iron filings from
sand
• Separates gravel (small
Sieve
pebbles) from sand
•
Separates
iron
filings
Magnet
from sand
Chromatography •
Separates pigments
in a mixture
• Separates solute
Evaporation
from solvent
Filtration • Separates dirt or
sand from water
Let’s summarize…
Explain the type of mixture that can be
separated by the following:
1. A sieve
2. Chromatography
3. A magnet
4. Evaporation
5. Filtration
Sand and iron particles that are similar
in size and color are mixed together
in a beaker. What would be the best
method of separating the particles?
1. Use tweezers to separate them.
2. Add water to the mixture.
3. Use a magnet to separate them.
4. Pour the mixture into a filter.
The substances in a mixture can be
separated by physical means because
1. no chemical change occurs when the
substances are combined.
2. the physical and chemical properties of
the substances change.
3. none of the properties of the substances
change.
4. the chemical, but not the physical,
properties of the substances change.
Identify whether each scenario is a physical
change or chemical change and support
your answer.
Physical change
No new substances were produced. It is still
glass even though it is broken.
Chemical change
New substances were produced because of the
baking.
Chemical change
CO2 and ash produced.
Physical change
No new substances were produced. It is still
water even though the ice is melting
Physical change
No new substances were produced. A substance
is just be grinded.
Chemical change
Iron oxides are produced as a result of the
rusting of the nail.
Chemical change
CO2 is produced and released when the tablet is
placed in water.
http://www.bbc.co.uk/schools/ks3bitesize/science/
chemical_material_behaviour/compounds_mix
tures/revise9.shtml