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Classifying Matter
TutorialClick to Begin…
Question 1 Question 2Question 3 Question 4Question 5 Question 6Question 7 Question 8Question 9 Question 10Question 11Question 12Question 13Question 14Question 15 Question 16Question 17 Question 18Question 19 Question 20
Click on Click on the next the next question:question:
Question 1
A soft drink is carbon dioxide gas dissolved in a flavored liquid. In a soft drink, the carbon dioxide is the…
a. Solution
b. Solute
c. Solvent
d. Dissolver
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Question 2
Students at Dulles High School want to separate a mixture of sand, sugar, perfume and vinegar. Which piece of equipment would they NOT use during this separation?
a. b.
c. d.
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Question 3
Which picture represents molecules
of an element?
a
b
c
g
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Question 4
Which of the following choices
represents a mixture with the lowest
energy?
a
d
e
f
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Question 5
Which picture best represents a solution
of gases?
b
e
f
i
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Question 6
Students performed an experiment to compare the dissolving time of several different salt samples. In a, 10
grams of salt is formed in one large cube. In b, 10 grams of salt is broken down into 10 smaller cubes. In c, 10 grams of
salt in broken into many very small cubes. Predict which sample will dissolve the fastest.
a
b
c
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Question 7
What inference can be drawn from the results of this experiment?
a. Increasing temperature will decrease dissolving time.
b. Decreasing a solute’s surface area will increase dissolving time.
c. Decreasing a solute’s surface area will decrease dissolving time.
d. Salt is insoluble in water.
Dissolved in 9 minutes
Dissolved in 3 minutes
Dissolved in 1 minutes
Here is the data collected in the experiment:
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Question 8
In the salt cube experiment…
a. Dissolving time is the independent variable, surface area is the dependent variable and salt is controlled.
b. Surface area is the independent variable, dissolving time is the dependent variable and amount of salt is controlled.
c. Shape of the salt is the independent variable, dissolving time is the dependent variable and the surface area is controlled.
d. There is no independent variable.
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Question 9
What is the meaning of the “plateau” at 100o on the above phase change diagram of H2O?
a. The H2O must have been removed from the heat source at that time.
b. The H2O molecules were not moving very fast during that time.
c. The heat applied to the H20 molecule was being used to break it down into hydrogen and oxygen.
d. The heat applied to the H2
0 was being used to overcome the attractions between the molecules rather than increase the temperature.
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Question 10
Which of the following statements is true?
a. As the water changes from a solid to a liquid, energy is absorbed.
b. As the water changes from steam to water, energy is absorbed.
c. The water molecules have more energy in the solid state than in the liquid state.
d. When the water changes into ice, energy is equal. Click here for
Tutorial
Question 11
Which of the following liquids has the highest viscosity?
a. Milk
b. Vegetable Oil
c. Corn syrup
d. Distilled water
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Question 12
a. Yes
b. No
A student wants to find out if a sample of metal she has is pure silver. She found the mass of the sample to be 100.99 g and the volume to be 78.3 cm3. Does she have pure silver?
Substance Density (g/cm3)
aluminum 2.7
steel 7.8
silver 10.5
gold 19.3
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Question 13
a. All will float on water
b. Rubbing alcohol and oil will float on water
c. Only rubbing alcohol will float on water
d. None will float on water – all will sink
Which of the above substances would float on water?
Substance Density (g/cm3)
aluminum 2.7
oil 1.9
Rubbing alcohol 0.92
gold 19.3
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Question 14
What is the solubility of a saturated solution of sodium chloride at 80°C?
a. 40 grams per 100 grams of water
b. 20 grams per 100 grams of water
c. 60 grams per gram of water
d. 40 grams per gram of water
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Question 15
How many grams of calcium chloride will dissolve in a saturated solution with 50 mL of water at 25°C?
a. 90 grams
b. 10 grams
c. 50 grams
d. 45 gramsClick here for
Tutorial
Question 16
You make a solution with 20 g of potassium nitrate dissolved in 100 g of water at 80°C. This solution is..
a. saturated
b. supersaturated
c. unsaturated
d. concentrated
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Question 17
Shelley collected a jar of water from a wave that was crashing onto Galveston beach. At first, the water was the same color and consistency throughout the jar. However, when she let it sit on her desk for a while, she noticed that some sand, rocks and dirt had settled to the bottom of the jar, while the liquid at the top became clear. What type of mixture is the beach water?
a. Pure
b. Heterogeneous
c. Homogeneous
d. Compound
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Question 18
What should it say at “A” is in the above chart?
a. Heterogeneous mixture
b. Homogeneous mixture
c. Pure Substance
d. Compound
Colloid Suspension Solution
A Heterogeneous Mixture Homogeneous Mixture
Particles are well-mixed Particles settle Particles are too small to be seen
Appears cloudy Filter paper will separate
Can be separated by simple physical means
Scatters light Scatters light Scatters light
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Question 19
Which of the above columns has a mistake?
a. Colloid
b. Suspension
c. Solution
d. None have mistakes
Colloid Suspension Solution
A Heterogeneous Mixture Homogeneous Mixture
Particles are well-mixed Particles settle Particles are too small to be seen
Appears cloudy Filter paper will separate
Can be separated by simple physical means
Scatters light Scatters light Scatters light
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Question 20
If you open a warm can of soda it fizzes and loses a larger amount of carbonation than a cold can of soda. Which of the following solubility curves explains the behavior of the carbonation?
a. c.
b. d.
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Tutorial 1
Remember…
A solute gets dissolved.
A solvent does the dissolving.
A solution is what is formed by dissolving a solute in a solvent.
For example, saltwater is a solution
The salt is the solute
The water is the solvent
TO MAKE A SOLUTIONBack to
Question
Read the descriptions that follow. If you answer no, then you will not use that instrument in the separation.
Tutorial 2
This…is the setup for a distillation. Distillation is used to purify a liquid or to separate two liquids from each other. Do you have two liquids to separate?
This…
is a magnet. If one of the substances is magnetic and the others are not, you can use this to separate the magnetic substance out. Do you have a magnetic substance?
Next page…
Tutorial 2
This…
is a hot plate, used for evaporation (boiling). If you have a solid dissolved in a liquid, you can boil it to get rid of the liquid and be left with the solid. Will you have a dissolved solid during this separation?
This…Is the setup for a filtration. If you have one solid that dissolves in a liquid and another that does not, you will filter the un-dissolved solid to separate it from the water. Will you have an un-dissolved solid in your lab?
Back to Question
Remember, elements are pure substances that are made of only one kind of atom. The following represent elements…
Notice that all of the diagrams only have one type of material in them.
An atom is a single piece, while a molecule is more than on piece connected together
molecule
atom
atom
atomsmolecule
molecules
Tutorial 3
Back to Question
Remember, mixtures are made of two or more pure substances that are not chemically joined together. The following diagrams represent mixtures…
Notice that all of the diagrams have more than one type of substance and the different
substances are not joined together.
Tutorial 4
Next page…
The question also asks about energy. Remember:
A Gas has a higher energy
than…
a Liquid, which has more energy
than…
a Solid.
Back to Question
Tutorial 5
A solution is another name for a homogeneous mixture. A homogeneous mixture is well-mixed. Look for a diagram that
has a pattern, such as these:
Remember, you are looking for a gas, so the particles in the mixture should be spread apart and moving fast.
Back to Question
Tutorial 6
In which of the samples is the surface area the greatest?
If surface area is high, what happens to the speed in which it dissolves? (Hint: does a lifesaver dissolve faster or slower if you chew it?)
So which one will dissolve fastest?Back to
Question
Tutorial 7
Your inference has to use the data collected in the experiment. The experiment tested surface area and dissolving time, so make sure your inference
includes those two factors!
Hint: The smaller the pieces are, the more surface area they have…
Back to Question
Tutorial 8
Independent variable: What is the one thing that the student changed from a to b to c?
Dependent variable: What were the students hoping that the independent variable had an effect on? What did they measure to get their results?
Controlled variable: What had to stay the same from a to b to c for it to be a fair experiment?
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Tutorial 9
A phase change diagram shows how the temperature of a substance changes when heat is added. Whenever you see plateaus on a phase change diagram, the substance in no
longer getting warmer. Instead, all of the heat energy is being used to change the substance from one phase to another.
Solid turning into liquidLiquid turning into gas
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Tutorial 10
Study the following:
When you move →, energy is absorbed by the molecules
When you move ←, energy is released by the molecules
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Tutorial 11
Viscosity can be described as the thickness or thinness of a liquid. A very viscous or high viscosity liquid is thick and a low viscosity liquid is thin. The definition of viscosity is resistance
to flow.
The following are all “thick” and resistant to being poured out. They all have a higher viscosity than
water…
Back to Question
Tutorial 12
Density is a property of a substance that can be used to identify a substance. To calculate density
take mass divided by volume. Then, compare your answer to the chart to see what substance
you have.
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Tutorial 13
7.8 > 1
So, the steel ball sinks.
Density of steel = 7.8 g/cm3
Recall that the density of water is 1 g/mL
0.89 < 1
So, the wood floats.
Density of wood = 0.89 g/cm3
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Tutorial 14
On a solubility curve, a saturated solution is represented by the line. To find the solubility of a saturated solution, just
read the information off of the graph. Be sure to check the y-axis for the correct units!For example, to find the solubility of KCl at 60o
C…
1. Find 60o on the x axis
2. Go straight up until you hit the
line for KCl.
4. Read your units off of the y-
axis label.
3. Go straight over and read
the grams of KCl off of the y-axis.
46
Back to Question
Tutorial 15
On a solubility curve, a saturated solution is represented by the line. To find the number of grams that will dissolve in a
saturated solution, just read the information off of the graph. Check the units, as this is usually per 100 grams of
water.
For example, to find the number of grams of KCl that will dissolve in 200 mL of water at 60o
C…
1. Find 60o on the x axis
2. Go straight up until you hit the
line for KCl.
4. Read your units off of the y-axis label. This is
per 100 mL of water.
3. Go straight over and read
the grams of KCl off of the y-axis.
46
For 200 mL of water, double your number (2 x 100 = 200).
So, 2 x 46 = 92 g of KCl
Back to Question
Tutorial 16
On a solubility curve, a saturated solution is represented by the line. Supersaturated solutions fall above the line.
Unsaturated solutions fall below the line.
Is a solution of 60 grams KCl dissolved in 100 mL of water at 50o C unsaturated, saturated or
supersaturated?
1. Find 50o on the x axis
2. Find 60 grams on the y axis
3. Where the two lines meet, draw
a point.
This point is above the line for KCl, so the solution is supersaturated.
Back to Question
Tutorial 17
The beach water is a little like this salad dressing. When the salad dressing sits in the fridge for a
while, the herbs and vinegar sink to the bottom, while the oil floats.
However, if we shake it up, it seems to be well-mixed again.
Even though it looks well mixed, it isn’t truly, since it doesn’t stay that way. So what kind of mixture is it that is not well
mixed?
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Tutorial 18
Remember, a colloid is something like shaving cream or fog. It is a mixture, but the particles are not dissolved.
Since the particles are not dissolved, it is not a homogeneous mixture. What kind of mixture is it?
Back to Question
Tutorial 19
Hint: It has to do with scattering light.
If a mixture scatters light, you can see a laser beam that passes through it.
Take a look at the above picture and determine if the colloid or the solution
scatters light.
colloid
solution
Back to Question
Tutorial 20
Recall from question 1 that soda is a solution of carbon dioxide dissolved in flavored
water.
Carbon dioxide is a gas. When you have a warm soda, the carbon dioxide cannot stay dissolved, and it escapes (the soda fizzes over). When it is colder, more of the carbon
dioxide can stay dissolved and so there is less fizzing over.
What will a graph of this look like?
Remember high temp = less carbon dioxide dissolved. Lower temp = more carbon dioxide
dissolved. Back to Question
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