Signs of Chemical Reactions

You know you a chemical reaction has occurred if 

• there is a precipitate.

• there is a color change.

• there is a temperature change.

• All of these answers are evidence.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

Evidence of a chemical reactions is anything that shows - 

• a new substance has formed

• a solid dissolved in a liquid

• interaction between 2 gases

• a change in the state of matter

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

One of the signs of a chemical reaction taking place is:

• Bubbles are produced 

• Reactants are not combining

• Products are not forming

• Color is not changing

Tags

NGSS.MS-PS1-2

A clear liquid from a flask is poured into another clear liquid in a beaker. Which of the following results of this procedure would indicate a new substance was formed?

• The level of the substance in the beaker is higher after the other liquid is added.

• A yellow solid forms and then settles to the bottom of the beaker.

• Small white crystals are left behind in the flask that held the first liquid.

• The mass of the combined liquids is greater than either original liquid.

Tags

NGSS.MS-PS1-2

Indicate whether the following is a sign of a chemical reaction or not.

Groups:

(a) Sign of Reaction

,

(b) Not a Sign of Reaction

• Density Change

• Color Change

• Shape Change

• Gas Production

• Emission of Energy

• Precipitate Formation

• Volume Change

• Change in Odor

• Phase Change

Tags

NGSS.MS-PS1-2

What are four signs of a chemical change?

b

c

d

e

Temperature Change

Increase in job worker.

Color Change

Solid's pertacipate form

Bubbles Form

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

Which one is NOT a sign that a chemical reaction has occurred?

• precipitate

• energy change

• unexpected color change

• dissolving

Tags

NGSS.MS-PS1-2

What are four signs of a chemical change?

b

c

d

e

Temperature Change

Solid's pertacipate form

Bubbles Form

Color Change

Increase in job worker.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

Which of the following is a sign that a chemical reaction has occurred?

• change in shape

• melting

• formation of a gas

• dissolving

Tags

NGSS.MS-PS1-2

This picture shows which sign that a chemical reaction has occurred?

• A powdery precipitate has formed

• The temperature has dropped

• Energy has changed

Tags

NGSS.MS-PS1-2