Pure Substances and Mixtures Unit Test
Name ____________________________
Explain the Particle Theory of Matter: (2)
Define and give an example of the following terms: (2 Each)
Matter
Pure substance
Mixture
Heterogeneous mixture
Homogeneous mixture (solution)
How does particle theory explain how a solute dissolves in a solvent? Why would a substance
dissolve in one solvent and not another? (2)
Circle the solute(s) and underline the solvent in the following solutions: (1 Each)
Lemonade crystals are mixed with water to make lemonade
Water, sugar, electrolytes, and food coloring are combined to make a bottle of sports drink
Analyzing Data: Saturated Solution
An experiment was conducted to determine how much salt is needed to saturate 100 mL of
water. Use the following data to answer the questions below.
Amount of Solute Added
Steps
Observations
10 grams
1
10 grams
2
10 grams
3
10 grams
4
10 grams
5
After stirring, the solute was
totally dissolved (no solute
was seen at the bottom of the
beaker).
After stirring, the solute was
totally dissolved (no solute
was seen at the bottom of the
beaker).
After stirring, the solute was
totally dissolved (no solute
was seen at the bottom of the
beaker).
After stirring, the solute was
totally dissolved (no solute
was seen at the bottom of the
beaker).
After stirring, some solute is
seen at the bottom of the
beaker.
1. Identify the solute and the solvent of the solution above. (2)
2. Indicate at which step the solution reached its saturation point. Justify your answer. (2)
3. What was the total amount of solute needed to saturate this solution? (1)
4. What is the concentration of the solution in step 3? (1)
You can purchase orange juice in one-litre containers. You can open and drink this juice without
adding water. There are also frozen juices to which you have to add water in order to drink
them. What term is used to describe the latter (second) type of solution: diluted or
concentrated? Explain your answer. (2)
What term might be used to describe a watery tasting drink solution: diluted or concentrated?
Explain your answer. (2)
Which of the following is a more concentrated solution? (1)
A. 45 grams per 100 mL
B. 37 grams per 100 mL
C. 12 grams per 100 mL
Matching (10)
___ Solvent
___ Insoluble
___ Solute
___ Dissolve
___ Dilute
___ Saturated
___ Mechanical Mixture
___ Unsaturated
___ Soluble
A. A solute that “disappears” in a
solvent
B. Mix well together
C. Mix together very well
D. Contains more dissolved material
than is required for saturation, at that
temperature
E. Something in which a substance
dissolves
F. Two or more pure substances in
same container
G. The mass of a dissolved material in
a specified amount of solvent
H. All spaces between solvent particles
filled with solute
I. The substance that gets dissolved
J. A tiny bit of solute in a large amount
of solvent
___ Concentration
List the three factors that affect the rate of dissolving: (3)
List the six techniques to separate mixtures discussed in class (6)
Use your list above to solve the situations presented in the scenarios below. (What is the best
way to separate the mixture? A scenario may require two steps) (5)
A person would like to make a glass of fresh pulpless orange juice.
Minute metal shards have fallen onto the sandy floor of a workshop. How could the owner clean
the sandy floor of the dangerous metal pieces?
You are stranded on a deserted island in the Pacific Ocean. There is no fresh drinking water,
only salt water from the ocean. How could you obtain drinking water?
To improve the icy road conditions, a sand-salt mixture has been used on the highways all
winter. The spring cleanup crew has scooped up the mixture and would like to use the sand for
road construction but the workers must first remove the salt. How could this be achieved?
Use the graph paper attached and the solubility data from the table below to create a
graph. (5) Then use the graph to answer the questions below.
Table 1. Solubility of sugar in water.
Temperature
(◦C)
Solubility of
sugar (g/100
mL water)
0
10
20
30
40
50
60
179
191
204
220
239
260
288
(a) How many grams of sugar will dissolve in 100 mL of water at 30◦C? At 35◦C? (2)
(b) At what temperature will 250 g sugar dissolve in 100 mL of water to form a saturated
solution? (1)
(c) If 180 g of sugar are dissolved in 100 mL of water at 18◦C, is the solution saturated?
Explain. (2)