Category 2 Science STAAR

A student observes ice forming on the edge of a school building. At what temperature did the water outside the school building most likely begin to change to ice?

• 100*C

• 32*C

• 25*C

• 0*C

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

The temperature at which a substance changes from liquid to gas (for water this is 100 degrees Celsius, 212 degrees Fahrenheit)

• boiling point

• melting point

• evaporation

• condensation

Tags

NGSS.MS-PS1-4

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

• Use a pair of tweezers to remove each grain of pepper

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

• Put the mixture in water and filter the pepper out of the water.

• Use a strainer with a fine wire mesh to remove the pepper

A mixture of beads was placed in a container, as shown below. The beads are of various sizes, and each one is made of plastic, glass or steel. The mixture would be easy to separate because all the beads....

• are less dense than water

• are solids

• have the same mass

• are attracted to magnets

Students prepare a solution of instant tea and place 30 mL of the solution in a Petri dish. Which answer choice best explains what happens to the solution when it is placed in a dry, warm location for 3 days?

• The solution will evaporate and the Petri dish will be empty.
• The solution will not change.
• The water will  evaporate and the instant tea will remain in the Petri dish.
• The water will condensate and the instant tea will remain in the Petri dish.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

How would you separate a mixture of sand and salt? 

• Mix them with water and let the water evaporate
• Mix them with water, pour the mixture through a sieve, then let the water evaporate
• Heat the sand and salt mixture for 5 minutes, then let it cool
• I would not do any of these because none of these options would work

Tags

NGSS.MS-PS1-2

Solubility is a measure of:

• The concentration of a homogeneous mixture
• The concentration of a heterogeneous mixture
• How easily a substance dissolves into another substance
• How easily a substance will dissolve a substance

Tags

NGSS.MS-PS1-2

Put the liquids in order from most dense to least dense?

• 4, 3, 2, 1
• 1, 2, 3, 4
• 3, 4, 2, 1, 
• 4, 3, 1, 2

Tags

NGSS.MS-PS1-2

Students collected data on the appearance of four substances and how they reacted when mixed with water. Which substances dissolved when mixed with water?

• A and B
• A and C 
• B and C 
• C and D

Tags

NGSS.MS-PS1-2

A student observed liquid wax dripping down the side of a burning candle. After putting out the candle’s flame, the student left the room. Several hours later the student observed that there was no longer any liquid on the side of the candle. Which statement explains what most likely happened to the liquid wax?

• The heat given off by the flame caused the candle wax to evaporate.
• The liquid wax changed back into a solid as it cooled.
• The liquid wax condensed and was absorbed by the candle.
• None of the above

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4