Chemical Changes and Evidence

What is a reactant?

• A substance present at the start of a reaction

• A substance formed after the reaction is complete

• A material that speeds up a reaction but is not used up

• Energy released as the reaction happens

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What is a product?

• A substance present at the start of a reaction

• A substance made as a result of a reaction

• A material that slows a reaction but is not used up

• Energy absorbed by the reaction

Tags

NGSS.MS-LS1-6

What does the Law of Conservation state?

• Matter and energy can be created but not destroyed during a chemical reaction

• Matter and energy is neither created nor destroyed; only transformed

• Energy and matter cannot change form during a reaction

• Matter and energy cannot be created but can be destroyed

Tags

NGSS.MS-PS1-5

NGSS.MS-PS3-5

Matter is changing all the time. Determine whether the change is a chemical change or a physical change.

Groups:

(a) Physical Change

,

(b) Chemical Change

• Digesting food
• Vinegar reacting with baking soda
• Chopping wood
• Salt dissolving

• Boiling water
• Silver tarnishing

• Milk sours (spoils)

• Breaking glass
• Iron rusts

• Melting ice
• Baking a cake
• Shredding paper

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

In a physical change, the molecules of matter are changed into a new combination.

• True

• False

A chemical change causes a recombination of chemical composition and identity of matter to form a new substance.

• True

• False

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

For the loaf rising and browning in a pan, what type of change is occurring?

• Physical change

• Chemical change

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

NGSS.MS-PS1-4

For paper being cut with scissors, what type of change is occurring?

• Physical change

• Chemical change

For a cup foaming when vinegar is mixed with baking soda, what type of change is occurring?

• Physical change

• Chemical change

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

For ice cubes turning to liquid water, what type of change is occurring?

• Physical change

• Chemical change

Tags

NGSS.MS-PS1-4