Chemical changes

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

• change in shape
• melting
• formation of a gas
• dissolving

Is hammering wood together to build a house a chemical or physical change?

• chemical
• physical

One cup of water is left outside for two days when it was checked there was only half a cup left. What happened?

• evaporation; chemical change
• condensation; physical change 
• evaporation; physical change
• condensation; chemical change

Rust on an iron bar is an example of chemical change.

• True 
• False

Is melting butter for popcorn a chemical or physical change?

• chemical
• physical

Is burning wood a chemical or physical change?

• chemical
• physical

A change in the size, shape, or state of matter.

• chemical change
• physical change
• chemical reaction
• electron change

What happens in ALL chemical changes?

• Change in state of matter
• A new substance is formed
• Bubbles are produced
• An explosion

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Is a a rusting bicycle a chemical or physical change?

• chemcial
• physical

Which of the following is NOT an example of a physical change?

• crumpled paper
• pencil sharpening
• shrunken clothing
• sour milk