A

Why is the toaster’s electrical cord covered in plastic?

• to make the toaster get hot faster

• because plastic is a poor conductor of heat

• to make electricity in the wire flow faster

• because plastic is a poor conductor of electricity

Which of the following materials could be used to complete the electric circuit and make the bulb light up?

• penny

• rubber band

• shoelace

• wooden toothpick

Tags

NGSS.MS-PS2-3

A student made a table to show some of the properties of a substance. Which property BEST identifies the substance as air rather than water?

• magnetism

• odor

• shape

• volume

Tags

NGSS.MS-PS1-2

A piece of copper is placed on a hot plate for one minute. When the copper is picked up with tweezers, the copper is as hot as the hot plate. The copper is said to be a(n)-

• thermal insulator

• thermal conductor

• electrical magnet

• none of the above

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

The graph shows how many grams of sugar dissolved in water of different temperatures. According to the graph, which of these is correct?

• Sugar changes color when it is dissolved in water.

• Sugar dissolves more easily in cool water than in warm water.

• Sugar causes water to become warmer.

• Sugar dissolves more easily in warm water than in cool water.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

The diagram represents four liquids of different densities. Which statement best describes the density of Layer C?

• Layer C is more dense than Layer A and less dense than Layer B.

• Layer C is more dense than Layer B and less dense than Layer D.

• Layer C is more dense than Layer B and less dense than Layer A.

• Layer C is more dense than Layer D and less dense than Layer B.

Tags

NGSS.MS-PS1-2

The diagram shows a ball in a beaker filled with water. Which statement best describes the relationship of the ball and the water?

• The water is less dense than the ball.

• The water and the ball are equally dense.

• The ball is less dense than the water.

• There is no relationship between the ball and the water.

The diagram represents four liquids that have different densities. If a liquid with a density represented by the diagram labeled X was added to the liquids, where would it be located?

• above Layer A

• between Layer A and Layer B

• between Layer B and Layer C

• between Layer C and Layer D

Tags

NGSS.MS-PS1-2

What is the atomic number of element A in the periodic table?

• 1

• 2

• 3

• 4

Which of the following is a characteristic of an acid?

• Tastes bitter

• Turns blue litmus red

• Feels slippery

• Reacts with metals to form bases