Mixtures & Solutions
Which example is a mixture in which you can still identify the different parts?
A. Salt completely dissolved in water
B. Trail mix containing nuts, cereal, and raisins
C. Sugar dissolved in tea
D. Food coloring dissolved in water
B. Trail mix containing nuts, cereal, and raisins
Which method would be best for separating paper clips from rice?
A. Magnet
B. Evaporation
C. Freezing
D. Melting
A. Magnet
Which action will usually make a solid dissolve faster in water?
A. Stirring
B. Stopping movement
C. Using larger pieces
D. Lowering temperature
A. Stirring
Which solution is more concentrated?
A. 2 g sugar in 100 mL water
B. 5 g sugar in 100 mL water
C. 1 g sugar in 100 mL water
D. 0.5 g sugar in 100 mL water
B. 5 g sugar in 100 mL water
Which is a physical property?
A. Ability to burn
B. Color
C. Ability to react with acid
D. Ability to rust
B. Color
Which statement BEST describes a solution?
A. Its parts are always easy to see.
B. One substance dissolves evenly throughout another substance.
C. It can never be separated.
D. It must contain two solids.
B. One substance dissolves evenly throughout another substance.
A student wants to recover gravel from water. Which method would work best?
A. Filtering
B. Evaporating
C. Stirring
D. Heating until boiling
A. Filtering
Why does crushing a sugar cube usually make it dissolve faster?
A. It changes sugar into a new substance.
B. It increases the amount of sugar.
C. It exposes more surface area to the water.
D. It removes the water.
C. It exposes more surface area to the water.
Four cups contain the same amount of water. Which has the greatest concentration of salt?
A. 1 spoon
B. 2 spoons
C. 4 spoons
D. No salt
C. 4 Spoons
Which property could help identify an unknown metal?
A. Its price
B. Its conductivity
C. Where it was found
D. Who owns it
B. Its conductivity
A student mixes sand and water. Which statement is true?
A. The sand dissolves completely.
B. The mixture is a solution.
C. The sand and water can be separated because the sand does not dissolve.
D. A new substance forms.
C. The sand and water can be separated because the sand does not dissolve.
A bowl contains iron filings and plastic beads. Which property could be used to separate them?
A. Magnetic attraction
B. Melting point of water
C. Solubility in oil
D. Room temperature
A. Magnetic attraction
Which setup would most likely produce the fastest dissolving?
A. A large crystal in cold, still water
B. Fine particles in warm, stirred water
C. Large pieces in cold, stirred water
D. Fine particles in cold, still water
B. Fine particles in warm, stirred water
A solution is too concentrated. What should a student generally add to make it less concentrated?
A. More solvent
B. More solute
C. More solid material
D. A magnet
A. More solvent
Two equal-size cubes are placed in water. Cube A sinks and Cube B floats. What property best explains
the difference?
A. Density
B. Color
C. Container shape
D. Room temperature
A. Density
Salt is stirred into water until it cannot be seen. Which description is most accurate?
A. The salt has disappeared permanently.
B. The salt and water formed a solution.
C. The salt changed into a new element.
D. The water became a solid.
B. The salt and water formed a solution.
A student has salt water and wants to collect the salt. Which process should be used?
A. Filtering
B. Evaporating the water
C. Using a magnet
D. Picking out the salt
B. Evaporating the water
A student tests whether water temperature affects dissolving time. Which variable should remain the
same?
A. Water temperature
B. Amount and particle size of the solute
C. The result
D. The question
B. Amount and particle size of the solute
Which solution has the lowest concentration?
A. 6 g sugar in 20 mL water
B. 6 g sugar in 40 mL water
C. 6 g sugar in 60 mL water
D. 6 g sugar in 80 mL water
D. 6 g sugar in 80 mL water
Which set contains only physical properties?
A. Magnetic, shiny, solid
B. Burns, rusts, reacts
C. Explodes, burns, dissolves
D. Changes chemically, rusts, burns
A. Magnetic, shiny, solid
Which gives the BEST evidence that a mixture has formed rather than a new substance?
A. The substances can be recovered using physical methods.
B. The mixture always changes color.
C. The mixture cannot be separated.
D. The substances lose all original properties
A. The substances can be recovered using physical methods.
A mixture contains large rocks, sand, and water. Which sequence would most reasonably separate all
three parts?
A. Magnet, then freeze
B. Filter out rocks and sand, then evaporate the water
C. Evaporate first, then use a magnet
D. Melt all three substances
B. Filter out rocks and sand, then evaporate the water
Two students test different particle sizes of the same substance. They use equal water volumes,
temperatures, and masses. Why is this a stronger investigation?
A. They changed several variables.
B. They controlled important variables so particle size can be compared fairly.
C. They guaranteed identical times.
D. They do not need data
B. They controlled important variables so particle size can be compared fairly.
Four solutions each contain 8 g of salt. Which is MOST concentrated?
A. 8 g salt + 20 mL water
B. 8 g salt + 40 mL water
C. 8 g salt + 60 mL water
D. 8 g salt + 100 mL water
A. 8 g salt + 20 mL water
A mystery solid has a known melting point, density, and conductivity. Why can these properties be
useful?
A. They help compare the unknown material with known substances.
B. They tell its price.
C. They prove it is always liquid.
D. They describe only its weight.
A. They help compare the unknown material with known substances.