Unit 4 Chemistry

A student places a piece of a potato into a container of hydrogen peroxide. One observation the student makes is that bubbles form around the potato. The presence of bubbles might indicate the formation of a new substance because bubbles -

• could show that a gas is forming.

• always rise to the top of a liquid.

• are almost always perfectly spherical.

• usually burst after a few minutes.

Tags

NGSS.MS-PS1-2

Matter changes state when...

• energy is added or removed

• energy is added

• energy is removed

• there is no energy

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

What state of matter is present at 50° C for water?

• solid

• liquid

• gas

• plasma

Tags

NGSS.MS-PS1-4

The particles in water move fastest in water that is _______________.

• boiling

• frozen

• liquid

• melting

Tags

NGSS.MS-PS1-4

If a substance is heated, what happens to its molecules?

• they slow down and move closer together

• the speed up and move closer together

• they slow down and move farther apart

• they speed up and move farther apart

Tags

NGSS.MS-PS1-4

When thermal energy is increased in a solid, what change in state is happening?

• Melting

• Evaporation

• Freezing

• Condensation

Tags

NGSS.MS-PS1-4

Molecules and compounds are created when multiple atoms bond together, but how are they different?

• Compounds have to have atoms from different elements bonded together

• Molecules have to have atoms from different elements bonded together

• They are the same and there is no difference

• Molecules are building blocks of compounds

Tags

NGSS.MS-PS1-1

What purpose do molecular models, drawings, and diagrams serve? (check all that apply)

• They allow us visual representations for things we can't normally see

• They make concepts more difficult to understand.

• They serve no purpose.

• They are fun to build.

Tags

NGSS.MS-PS1-1

Ionization energy is the...

• energy needed to remove the outermost electron.

• ability of an atom to attract electrons from another atom.

How many valence electrons does a halogen have? 

• 1

• 2

• 7

• 8