Grade 8 Science PM3 Practice

Which of the following presents a safety hazard while working in the science laboratory?

• knowing how to use equipment

• wearing safety goggles

• following directions

• working alone

What is the proper safety response to a trash-can fire in a lab?

• throw chemicals on the fire

• leave the room to seek help

• watch the fire to see if it spreads

• use the appropriate fire extinguisher

The safety equipment shown above is used in situations involving

• chemical spills

• fires

• broken glass

• physical injuries

Ryan and Amy wanted to check if a solid substance could form an acid or a base. In what order should she do the following steps?

A. Test with blue litmus paper,

B. Dissolve the substance in water

C. Look at any changes in the color of the litmus paper

D. Grind some of the substance to make a powder.

• A D B C

• B A C D

• C B A D

• D B A C

Tags

NGSS.MS-PS1-2

Two substances are mixed in four beakers, and a thermometer is placed in each beaker. The thermometers are checked every minute for five minutes, and the temperature is recorded in the table.

Which beaker shows the greatest temperature change over five minutes?

• A: Beaker A

• B: Beaker B

• C: Beaker C

• D: Beaker D

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

NGSS.MS-PS3-4

A very large redwood tree is measured to be about 100 units tall. Which unit is the most appropriate to use?

• millimeters

• centimeters

• meters

• kilometers

The fine lead used in mechanical pencils has a very tiny size. Its diameter is about 0.5 units. Which unit of measurement best represents this?

• 0.5 centimeters

• 5.0 centimeters

• 0.5 millimeters

• 5.0 millimeters

The most appropriate scientific units for measuring the volume of the liquid in the petri dish would be

• milliseconds

• milliliters

• millimeters

• milligrams

Alex tested three brands of batteries to learn which would last the longest in a flashlight. He placed two brand "A" batteries in a flashlight, turned the flashlight on, and measured the time that the light shined. He repeated the experiment with battery brands "B" and "C" using the same flashlight. He recorded the data on the bar graph below.

Based on the bar graph titled "Battery Experiment Results," which of these is an accurate conclusion that Alex can make about the batteries he tested?

• Brand "C" batteries lasted twice as long as brand "A" batteries.

• Brand "C" batteries lasted three times longer than brand "B" batteries.

• The light was twice as bright with brand "A" batteries than with brand "B" batteries.

• The light shined three times farther with brand "C" batteries than with brand "B" batteries.

Which conclusion is best supported by the data in the table?

• Metal objects are more likely to float in water.

• The color of an object determines if it will sink or float in water.

• The shape of an object determines if it will sink or float in water.

• An object floats in water if its mass is less than its volume.