Cambridge Primary 5 Science: Dissolving and Solutions This lesson quiz helps learners explain dissolving, solutions, solubility and how to investigate factors that affect dissolving.
Use the model. What is the solute in salty water?
A
filter paper
B
salt
C
water
D
cup
Explanation
The solute is the substance that dissolves.
What is the solvent in salty water?
A
salt
B
air
C
water
D
glass
Explanation
The solvent is the liquid that dissolves the solute.
What is a solution?
A
a new animal
B
a separated solid
C
any solid only
D
a mixture formed when a solute dissolves in a solvent
Explanation
A solution is a uniform mixture.
Which substance dissolves in water?
A
sugar
B
sand
C
plastic beads
D
gravel
Explanation
Sugar is soluble in water.
Which substance is insoluble in water?
A
salt
B
sand
C
some drink powder
D
sugar
Explanation
Sand does not dissolve in water.
When salt dissolves, what happens to it?
A
It disappears from existence
B
It turns into sand
C
Its particles spread through the water
D
It becomes a gas only
Explanation
Dissolving spreads particles in the solvent.
How can you get salt back from salt water?
A
sieve it
B
use a magnet
C
filter it with ordinary paper
D
evaporate the water
Explanation
Evaporation leaves salt crystals behind.
What is solubility?
A
how much solute can dissolve in a solvent
B
how fast a shadow moves
C
how loud a material is
D
how magnetic water is
Explanation
Solubility describes dissolving capacity.
What is a saturated solution?
A
one with no solvent
B
one that cannot dissolve more solute at that temperature
C
one that has no particles
D
one that is always red
Explanation
Extra solute remains undissolved.
Which factor often makes sugar dissolve faster?
A
removing water
B
cooling strongly
C
stirring
D
using larger crystals only
Explanation
Stirring brings fresh solvent to the solute surface.
Which factor often makes sugar dissolve faster?
A
no movement
B
larger lumps only
C
less solvent
D
warmer water
Explanation
Higher temperature usually speeds dissolving.
Which factor often makes a solid dissolve faster?
A
smaller pieces
B
less contact area
C
bigger lumps
D
not touching solvent
Explanation
Smaller pieces have greater surface area.
In a fair test of temperature on dissolving time, what should change?
A
cup colour
B
temperature only
C
amount of solute and stirring together
D
every variable
Explanation
Only the independent variable should be changed.
What could be the dependent variable in that test?
A
type of cup kept the same
B
same mass of sugar
C
time taken to dissolve
D
amount of water kept the same
Explanation
This is the measured result.
Why keep the amount of water the same?
A
to remove the solute
B
to stop particles
C
to make the answer bigger
D
to make the test fair
Explanation
Controlled variables make comparisons valid.
Which is not a solution?
A
sand and water mixture
B
sugar water
C
salt water
D
copper sulfate solution
Explanation
Sand remains suspended or settles; it does not dissolve.
Why might clear water not be pure?
A
Clear means empty
B
Dissolved substances can be invisible
C
Water has no particles
D
All clear liquids are pure
Explanation
Solutions can look clear.
Which method tells whether a solid dissolved or settled?
A
listen for sound
B
ask if it is heavy
C
observe after stirring and leaving it to stand
D
check if it is colourful only
Explanation
Insoluble solids settle or remain visible.
What does "concentrated" mean for a solution?
A
only solid particles
B
a gas with no liquid
C
no solute
D
a lot of solute dissolved in a given amount of solvent
Explanation
Concentration compares solute amount with solvent amount.
Which summary is correct?
A
Dissolving forms a solution but the solute can often be recovered
B
Dissolving destroys matter
C
All solids dissolve in water
D
Filtering always removes dissolved substances
Explanation
Dissolving is usually reversible for many simple solutions.