Mixtures & Solutions (STAAR released items)

A student stirs 15 grams of each substance listed below into 200 milliliters of water to form four different mixtures. The student then tries to separate the water from each mixture by pouring the mixture through a kitchen tea strainer.

Which mixture can the student separate most easily with the strainer?

• salt and water

• gravel and water

• shampoo and water

• sugar and water

Tags

NGSS.MS-PS1-2

Some ways to separate mixtures are listed in the box.

A Student is given a beaker containing gravel and water. Which of these ways could the student NOT use to separate the gravel from the water?

• 1

• 2

• 3

• 4

Some people add sugar to their hot tea. Which property of the sugar remains the same when the sugar is in the tea solution?

• The taste of the sugar remains the same.

• The size of the sugar crystals remains the same,

• The color of the sugar remains the same.

• The texture of the sugar remains the same.

A student made a mixture using equal amounts of salt and pepper. The salt grains were about the same size as the pepper grains. What should the student do to most easily separate the pepper from the mixture?

• Use tweezers to remove each grain of pepper.

• Run a magnet through the mixture to attract the pepper.

• Put the mixture in water and then use a paper filter (coffee filter) to remove the pepper.

• Use a strainer with a fine wire screen to remove the pepper.

A mixture of beads was placed in a container. The beads are of various sizes, and each one is made of either plastic, glass, or steel.

The mixture would be easy to separate, because _____________.

• all the beads are less dense than water.

• all the beads are solids.

• all the beads have the same mass.

• all the beads are attracted to a magnet.

A beaker with 115 mL of solution has a temperature of 21 degrees Celsius. The solution contains 5 g of salt and 115 mL of water. Students add two ice cubes to the solution and then stir the solution for 3 minutes.

Which properties of the solution changed as the ice cubes melted?

• The color and physical state of the solution changed.

• The temperature, mass, and volume of the solution changed.

• The temperature, mass, and volume of the salt changed.

• The physical state (solid, liquid, or gas) and temperature of the solution changed.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

NGSS.MS-PS3-5

For an investigation a student put 100 mL of water at room temperature into each of three beakers. Then the student added a coin to Beaker R, 3 g of powdered drink mix to Beaker S, and 10 mL of lamp oil to Beaker T. The student stirred the contents of the beakers and then left them sitting on a lab table for 5 minutes.

Which diagram shows what the student most likely observed in each of the beakers after 5 minutes?

• 
• 
• 
• 

Tags

NGSS.MS-PS1-2

A student combined (mixed) powdered paint with water to make a small amount of blue liquid paint mixture. The student left the paint mixture in an open container. Several days later the student found the container and observed that changes had occurred (happened). What most likely happened to the mixture?

• The container was completely empty after the mixture evaporated into the air.

• The paint evaporated, leaving only clear water in the container.

• The water evaporated, leaving only a dry blue solid in the container.

• The paint mixture was lighter in color after some water evaporated.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

A student adds 10 grams of four different powders into four different beakers. The student then adds 100 mL of water to each beaker, stirs the mixtures, and allows them to sit for half an hour before recording observations. Which question is the student most likely trying to answer with this investigation?

• The student wants to know at what temperature the substances dissolve.

• The student wants to know how much water is needed to cause a substance to change state.

• The student wants to know what causes a substance to sink when put in water.

• The student wants to know which substances will dissolve in water.

When a powdered drink mix was added to water, the liquid turned orange. A student decided the taste was too strong, so he poured out half the liquid and added more water. Which of the following most likely occurred (happened) when more water was added?

• The physical state of the liquid changed.

• The orange color of the liquid became lighter.

• The liquid had a sweeter taste.

• Nothing changed.