Mixtures Test (1)

Which tool or technique would best separate a mixture of gravel and sand?

• Sieve

• paper filter

• magnet

• evaporation

Answer explanation

The sieve would stop the gravel because it is larger and allow the sand to pass through because they are smaller.

A mixture of pencils and pens can be separated easily because both pencils and pens—

• are magnetic.

• cannot pass through a sieve.

• are solid.

• can be evaporated.

Answer explanation

Pencils and pens are both solid therefore easy to see and separate.

A student dissolved powdered drink mix in cold water to form a sweet, purple, grape-flavored solution. To make the solution’s taste less strong, the student added more water to the solution. How did the physical properties of the solution changed when more water was added?

• The taste

• The color

• The physical state

• The volume

A saltwater solution can be separated easily because—

• salt evaporates when boiled, leaving behind water.

• salt can be removed from the solution using tweezers.

• water evaporates when boiled, leaving behind salt.

• water passes through a sieve, leaving behind the salt.

9. A student mixed together 10 grams of salt, 10 grams of sand, and 500 milliliters of water in a beaker. After stirring, the student allowed the mixture to sit for 20 minutes before recording observations. What did the student most likely observe?

• Both the salt and sand settled to the bottom of the beaker.

• Both the sand and salt dissolved in water.

• The salt floated while the sand sank.

• The salt dissolved and the sand settled to the bottom of the beaker.

A beach is made up of minerals, tiny shells and skeletons of marine life, and even microscopic pieces of plastic. Which statement correctly describes this mixture?

• The ingredients in the mixture dissolve to form a solution.

• The ingredients in the mixture maintain their physical properties.

• The mixture includes solutes and a solvent.

• The mixture can be easily separated using evaporation.

Which of the methods would separate a mixture of steel paperclips and plastic paper clips?

• Methods 1 and 4 only

• Method 4 only

• Methods 1, 3, and 4 only

• Method 2 only

Three mixtures are listed. Which of the mixtures can be separated by placing the mixture in a beaker of water?

• Mixture 1 because corks float in water and ping pong balls sink

• Mixture 2 because plastic beads float and glass beads sink

• Mixture 3 because iron nails and gravel both sink in water

• Mixture 1 because corks and ping pong balls both float in water

A teacher made lemonade for a class party. He stirred lemon juice and sugar into water. Which property of the sugar remained the same when it was dissolved in the lemonade solution?

• texture

• taste

• color

• none of the above

A lab team followed the procedure below:

1. Stir 50 grams of salt into 1,000ml of water. 2. Boil the saltwater solution in a pan using a hot plate. 3. Remove from heat after all water has evaporated.

How many grams of salt can the lab team expect to find in the pan after Step 3?

• 0 grams

• 25 grams

• 50 grams

• 100 grams