Chemical Reactions

According to the Law of Conservation of Mass, 3 atoms of calcium react to produce 6 atoms of calcium.

• true

• false

Tags

NGSS.MS-PS1-5

Energy is needed to break chemical bonds in chemical reactions.

• true

• false

Tags

NGSS.HS-PS1-4

An endothermic reaction is one in which more energy is absorbed than is released.

• true

• false

Tags

NGSS.MS-PS1-4

All chemical reactions occur at the same rate.

• true

• false

Tags

NGSS.HS-PS1-5

Activation energy is the minimum amount of energy needed for a chemical reaction to begin.

• true

• false

Tags

NGSS.HS-PS1-4

When a chemical reaction contains the same number of atoms on both sides, the equation is balanced.

• true

• false

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Lowering the temperature slows down most chemical reactions.

• true

• false

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

The rate of reaction is the speed at which products form or reactants disappear.

• true

• false

Tags

NGSS.HS-PS1-5

Which of the following changes is chemical rather than physical?

• water is boiled

• aluminum foil is crumpled

• glass is shattered

• wood is burned

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Each substance written to the right of the arrow in a chemical equation is a ___

• reactant

• product

• precipitate

• catalyst

Tags

NGSS.MS-PS1-5