Evidences of Chemical Reaction

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

You know that a chemical reaction is occurring here because you see __________________ . (Pick 3)

• purple color

• smoke

• ice formation

• fire

• a yellow precipitate

Tags

NGSS.MS-PS1-2

Which statement best describes evidence that a chemical reaction occurs as a cake bakes?

• The water in the cake batter evaporates.

• The cake rises as gas bubbles form in the baking cake.

• The cake takes the shape of the container in which it is baked.

• The water in the cake batter is used to keep the cake moist as it bakes.

Tags

NGSS.MS-PS1-2

In a container, a solid consisting of clear crystals is combined with a blue liquid and the following observations are obtained.
 How many of the listed observations indicate a new substance was formed?

• 1

• 2

• 3

• 4

Tags

NGSS.MS-PS1-2

Which observation(s) might be used as evidence that a chemical reaction occurred?

• Color change

• Odor change

• change in temperature

• All of the above

Tags

NGSS.MS-PS1-2

What evidence(s) of a chemical reaction do you see in the pictures? (Select all that are correct)

• Gas

• Precipitate

• Color Change

• Giving off light

Tags

NGSS.MS-PS1-2

The only sure evidence of a chemical reaction is.... (a)  

• the formation of a gas.

• a color change.

• the production of a new substance.

Tags

NGSS.MS-PS1-2

Which observation(s) might be used as evidence that a chemical reaction occurred?

• Color change

• Odor change

• Properties change

• All of the above

Tags

NGSS.MS-PS1-2

The student observed that the temperature changed from 25°C to 23°C when the solutions were combined and that a white substance rapidly formed and settled to the bottom of the container. What most likely happened to produce these results?

• One of the original compounds came out of solution.

• The solutions reacted chemically.

• Some of the water froze into ice crystals.

• Rapid evaporation of water occurred, leaving a solid.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

The student inferred that a chemical reaction occurred. What evidence supports this

inference?

• A dark solid formed on the zinc metal.

• The zinc metal remained silver-colored and shiny.

• The CuSO solution turned blue when the zinc metal was added.

• None of these

Tags

NGSS.MS-PS1-2