Chemistry Post-Test Review

What does this safety sign mean?

• radioactive

• biohazard

• poison

• flammable

Which of the following is the best way to clean your hands after using chemicals in a laboratory experiment?

• Rinse your hands with distilled water.

• Use a generous amount of hand sanitizer.

• Wash your hands with soap and water.

• Wipe your hands with a wet paper towel.

Match the following actions with the most appropriate handling of excess chemicals after a laboratory exercise.

• What to do if you want to follow proper laboratory safety and disposal procedures?

• Wash the chemicals down the sink with a large amount of water.

• What to do if you want to disregard environmental safety?

• Leave the chemicals at the lab station for the next group.

• What to do if you want to risk chemical contamination?

• Read the MSDS for proper disposal of each unused chemical.

• What to do if you want to improperly manage laboratory safety?

• Pour the unused chemicals back into their original containers.

Tags

NGSS.MS-ESS3-3

Which statement is correct about scientific theories?

• Theories are educated guesses about the results of an experiment.

• Theories are well-established explanations for experimental observations.

• Theories can explain experimental results, but cannot predict results in advance.

• Theories have been repeatedly proven and are considered to be absolute facts.

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-4

Which device will most accurately measure the volume of a liquid?

• Beaker

• Burette

• Erlenmeyer flask

• Volumetric flask

Given 1 inch=2.54 cm, which value best represents the number of centimeters in 5.660 ft?

• 172.6 cm

• 102.4 cm

• 0.5533 cm

• 0.003617cm

During an investigation, a student combined two substances as shown above. The student observed a decrease in temperature when the substances were combined. A milky substance was produced and fell to the bottom of the flask. What is the most likely reason for these results?

• A portion of the substances crystallized.

• A solid appeared after the liquid evaporated.

• The combined substances chemically reacted.

• A portion of the substances dissolved.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

NGSS.MS-PS1-5

Match the following properties with their classification as either an intensive or extensive property.

• Color of an object

• Silver

• Appearance of an object

• Metallic

• Amount of matter in an object

• Melting point

• Temperature at which an object changes from solid to liquid

• Mass

Indefinite shape and definite volume describe which state of matter?

• Liquid state

• Solid state

• Plasma state

• Gaseous state

Tags

NGSS.MS-PS1-4

The following table displays the physical properties of some common elements. A sample of chlorine and a sample of sodium were placed in a test tube and heated over a flame. The properties of the product are listed below: - Density = 2.17 g/cm³ - White crystalline solid - Poor conductor of electricity in solid form - Dissolves in water - Non-toxic According to the information and Properties of Elements table above, the white substance is classified as a(n) —

• homogeneous mixture

• heterogeneous mixture

• compound

• element

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2

NGSS.MS-PS1-5