L3 - Chemical Changes

When I bake bread, the recipe says to let dough rise. Is that a chemical or physical change?

• Physical Change

• Chemical Change

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

Select three clues that a chemical change has happened.

• Created an odor

• Shape change

• Changed color

• Released gas

If substance A is 30 grams and substance B is 20 grams. When I combine them, the total mass will be 50 grams because of:

• Physical Change

• Chemical Change

• Conservation of Matter

• Color Change

I measure the mass before my campfire and after my campfire. Why did the mass decrease?

• The reaction destroyed some matter.

• The particles in the fire exploded.

• The chemical reaction of the fire, created gas and ash, which escaped into the atmosphere.

• The fire melted the particles, causing them to become smaller.

Rust is a chemical changed caused by

• rain

• oxygen

• oxygen and moisture in the air

• age

Below are results of my experiment mixing two substances. Select the two results that are chemical changes.

• The sugar dissolved into small particles.

• Gas bubbles formed.

• Broke into small pieces.

• Turned into a solid.

A chemical change

• will never change colors.

• will always change colors.

• produces a new substance.

• will always create gas.

Tags

NGSS.MS-PS1-2

To back up your data means to

• support

• change

• delete

• resolve

Conservation of Matter

• states that in chemical or physical changes, the total mass does change.

• states that in chemical or physical changes, the total mass does not change.

A chemical reaction is

• observing one or two substances changing into new substances.

• so cool.

• the creation of extra mass.

• always bubbling.