Test review chemistry 8th

A student creates models using gum drops of different colors to model matter. An individual gum drop represents a(n) _______.

• Mixture

• Compound

• Element

• Solution

Tags

NGSS.MS-PS1-1

Two gum drops of different colors stuck together with a toothpick represent a(n) _______.

• Element

• Mixture

• Compound

• Homogeneous mixture

Tags

NGSS.MS-PS1-1

Different colored gum drops not stuck together represent a(n) _______.

• Compound

• Mixture

• Solution

• Element

Which statement best describes an element?

• A substance made of one type of atom

• A non-uniform combination of particles

• A molecule of H2O

• Two or more different atoms chemically combined

Which describes a compound?

• A hydrogen molecule (H2)

• A pure substance made of only one atom type

• A water molecule (H2O)

• A non-uniform mixture

Tags

NGSS.MS-PS1-1

Which best describes a heterogeneous mixture?

• A pure substance

• Evenly distributed particles

• Visible distinct parts

• Only one atom type

Which best describes a homogeneous mixture?

• A pure substance

• Evenly mixed throughout

• Non-uniform combination

• A single type of atom

In the reaction vinegar + baking soda → new substances, (NaHCO3 + HC2H3O2 → NaC2H3O2 + H2O + CO2) which atoms appear on both sides?

• Carbon, Hydrogen, Oxygen, Sodium

• Nitrogen, Carbon dioxide, Water

• Hydrogen, Nitrogen, Carbon, Oxygen

• Sodium, Argon, Oxygen

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which statement about chemical reactions is correct?

• Atoms are rearranged to form a new substance

• New atoms are created

• Atoms are destroyed

• Nucleus of atom changes

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Orange juice has vitamin C and a tangy taste. If tested with pH paper, its pH would most likely be:

• 12

• 9

• 7

• 3