Chemical Reactions

Which of the following provides the best evidence that a chemical change is taking place?

• Liquid changes color when mixed with another liquid.

• A solid scratches the surface of another solid.

• Steam rises from the surface of a liquid.

• A metal object becomes shorter when it is cooled.

Tags

NGSS.MS-PS1-2

In which of the following situations is a sugar cube undergoing a chemical change?

• when it is crushed

• when is is mixed with salt

• when it is burned

• when it is dissolved in water

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What are the five signs t hat a chemical change is occurring?

Tags

NGSS.MS-PS1-2

What is a chemical reaction?

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What are reactants?

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-5

What are products?

Tags

NGSS.MS-LS1-7

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Reactants are listed ​ (a)   of a chemical formula.

• at the beginning
• at the end

Products are listed ​ (a)   of a chemical equation.

• at the end
• at the beginning

Which is not an example of a chemical change?

• heat is given off

• light is released

• bubbles are formed

• a substance evaporates

Tags

NGSS.MS-PS1-2

A substance is heated and is bubbling. As it was heated, a precipitate formed and it changed color. Did a chemical reaction occur? Give evidence to support you claim.

Tags

NGSS.MS-PS1-2