The video tutorial explains the differences between physical and chemical changes. Physical changes alter the appearance but not the composition of a substance, such as breaking graham crackers or melting a popsicle. Chemical changes involve the rearrangement of molecules, like baking a cake or cooking meat. The video also covers how to identify chemical changes through signs like bubbles, smell, and color change, and discusses the reversibility of these changes.

What remains unchanged in a physical change?

• Chemical composition

• Both chemical composition and molecular bonds

• Molecular bonds

• None of the above

What happens to a substance in a physical change?

• It becomes a new substance

• It changes chemical structure

• It changes color

• It changes state

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NGSS.MS-PS1-4

What can be physically separated in a mixture?

• Molecular bonds

• Mixture components

• Compounds

• Elements

What indicates a chemical change?

• Change in shape

• Formation of a new substance

• Change in state

• All of the above

Tags

NGSS.MS-PS1-2

Which is a sign of a chemical change?

• Expanding of a balloon

• Burning of wood

• Dissolving of sugar

• Melting of ice

Tags

NGSS.MS-PS1-2

What does a change in smell usually indicate?

• All changes

• No change

• Physical change

• Chemical change

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What forms when milk is left out overnight?

• None of the above

• Dissolved substances

• Precipitate

• Bubbles

Tags

NGSS.MS-PS1-2

What is easier to reverse?

• Both are equally easy

• Neither can be reversed

• Chemical change

• Physical change

What happens to molecular bonds in a chemical change?

• They only break

• They remain unchanged

• They only form new bonds

• They break and form new bonds

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which of the following is a physical change?

• Baking a cake

• Rusting of iron

• Burning paper

• Freezing water