Name: _____________________________________________________
Year 8 Revision
1. When ice is heated, the water molecules begin to move faster and _____________apart. When
they are far enough apart the attraction weakens and the ice____________.
As water molecules in the liquid for are heated the particles continue to move further apart and the
attraction between them becomes even____________. Water molecules then have so much energy
that they leave the surface of the liquid water and become water_________, a gas. This process is
called_________________.
In the case of Carbon Dioxide, at normal air pressure, liquid CO2 cannot form. As solid CO2 (dry ice) is
heated the particles go directly to a gaseous state. This process is called________________.
When water vapour particles are cooled they vibrate less and move ________together. When they are
close enough, the particles begin to attract each other and the water vapour turns to liquid water. This
process is called_______________.
As liquid water is cooled the particles again vibrate ________and move closer together. When the forces
of attraction become strong enough the water molecules form solid ice crystals. This process is
called____________.
weaker
sublimation
closer
freezing
melts
evaporation
condensation
further
vapour
less
2.
Solid
Liquid
In the boxes above draw the arrangement of particles for each state (phase).
Gas
3. For each of the following, state whether they are an element or compound.
Al ____________________
CO2 _____________________________ Be _________________________
NaCl _________________
Au____________________ C ___________________________
Explain how you made your decision as to whether a chemical formula is for an element or compound.
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
4. List 3 signs of a chemical change.
_______________________________
______________________________
______________________________
5. Give 3 examples of a physical change.
_______________________________
_______________________________
_______________________________
6. Which state(s) of matter are unable to be compressed?
_____________________________________________________________________________
7. What is the difference between compounds and mixtures? Give an example of each.
_____________________________________________________________________________
8. Particles move the fastest in which state of matter?
_____________________________________________________________________________
9. The word “flow” can be applied to which states of matter? Justify your decision.
_____________________________________________________________________________
_____________________________________________________________________________
10. True or False: Particles are always moving in a gas but stationery in a solid.
_____________________________________________________________________________
11. Define the term precipitate.
_____________________________________________________________________________
12. Contrast the terms endothermic and exothermic and give examples of each.
_____________________________________________________________________________
13. In which states of matter does diffusion occur?
_____________________________________________________________________________
14. Why do substances expand when they are heated?
_____________________________________________________________________________
15. Give an example of how the expansion of solids is used in the world around us.
_____________________________________________________________________________
17. What would happen to a balloon if you put it in the freezer? Why?.
_____________________________________________________________________________
MULTIPLE CHOICE QUESTIONS
1.
An element is:
A
an incredibly small particle, too small to be seen with a normal microscope
B
a substance that can be chemically broken down into simpler substances
C
a building block of all matter
D
a substance that cannot be chemically broken down into any simpler substances
2. The periodic table is organised into:
A
rows of elements with similar properties, increasing in atomic size down the columns
B
columns of elements with similar properties, increasing in atomic size down the columns
C
metals on the right and non-metals on the left
D
no specific pattern other than increasing atomic size
3. Water, H2O, is:
A
a compound because it cannot be broken down into simpler substances
B
an element because it cannot be broken down into simpler substances
C
a compound because it can be broken down into simpler substances
D
an element because it can be broken down into simpler substances
4. Alloys
A
include: brass, stainless steel, solder
B
galvanising and coating are all the same
C
galvanising and coating are all ways to minimise physical changes
D
all of above
5. In a chemical reaction:
A
Atoms in molecules rearrange to form new molecules.
B
Some atoms are lost.
C
Some new atoms are added.
D
Energy is ALWAYS given off.
6. In a chemical reaction between elements:
A
the atoms in the elements are rearranged to form a new substance called a compound
B
some reactant matter is always lost
C
some product matter is always created
D
the compound product always has the same properties as the elements
7. A glucose molecule C6H12O6 is made up of the following:
A
Twelve cobalt atom, six hydrogen atoms and six oxygen atom
B Six carbon atoms, twelve hydrogen atoms and six oxygen atoms
C
One carbon atom, two hydrogen atoms and one oxygen atom
D
Six copper atoms, twelve hydrogen atoms and six oxygen atoms
8. Which scenario described below indicates a physical change has occurred in a substance?
a) A bowl of water is placed in the freezer.
b)
Bacon and eggs are cooked for breakfast.
c)
Glow sticks are snapped, shaken slightly and then begin to glow.
d)
While out camping, wood is lit in a campfire and is used for cooking.
9. Which one of the following combinations of terms defines the changes of state between solids and
liquids?
a)
Sublimation and deposition
b)
Evaporation and condensation
c)
Melting and freezing
d)
Distillation and condensation
10.
Which one of the following combination of terms defines the changes of state between solids and
gases?
a)
Sublimation and deposition
b)
Evaporation and condensation
c)
Melting and freezing
d)
Distillation and condensation
11.
When a water jug is placed in a refrigerator, the liquid in the container is cooled. During this process
the particles in the liquid:
a)
move to the bottom of the jug
b)
lose their energy and move more slowly
c)
have cold energy added to them
d)
get smaller and smaller.