7.1 - 3 Characteristics of Chemical Reactions

Two clear chemicals combine. The solution turns yellow and gets cold. What evidence suggests that a chemical change took place?

• There is no evidence.

• The solution turned yellow.

• The solution got cold.

• The solution both turned yellow and got cold.

Tags

NGSS.MS-PS1-2

The smallest particle of an element, made of electrons, protons, and neutrons

• Properties

• Reactant

• Atom

• Chemical process

Tags

NGSS.MS-PS1-1

A substance that takes part in and undergoes change during a reaction

• Properties

• Reactant

• Atom

• Chemical reaction

Tags

NGSS.MS-PS1-2

Sodium and chlorine react to form salt. How do we know a chemical reaction has taken place at the atomic level?

• Both substances have a positive charge.

• Sodium and chlorine regroup to form a new molecule.

• One of the atoms is bigger than the other.

• Chlorine is a gas and sodium is a solid.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Method or means of changing one or more chemicals or chemical compounds

• Chemical process

• Atom

• Properties

• Reactant

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

The process by which one or more substances change to produce one or more different substances

• Chemical process

• Chemical reaction

• Properties

• Reactant

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Why is a saltwater solution only a physical change?

• The water atoms rearrange when combined with salt.

• The salt cannot be separated from the water after they mix.

• The salt atoms and water recombine to make a new substance.

• The salt atoms and water atoms do not recombine to make a new substance.

Tags

NGSS.MS-PS1-2

Which of the following is NOT an indicator (evidence) of a chemical reaction?

• Precipitate formation

• Light being produced

• Change in state of matter

• Change in temperature

Tags

NGSS.MS-PS1-2

How are fireworks an example of chemical reactions?

• The chemicals do not change as they explode.

• They are made of chemicals.

• Heat, light, and sound are given off.

• Fireworks are not examples of chemical reactions.

Tags

NGSS.MS-PS1-2

Physical and chemical characteristics of matter used to describe or identify a substance

• Chemical process

• Atom

• Reactant

• Properties

Tags

NGSS.MS-PS1-2