Chemical and Physical Changes (3.2)

Front

What is the law of conservation of mass?

Back

Mass cannot be created or destroyed in a chemical reaction.

Front

Give an example of a chemical change. Options: Melting of ice, Mixing of salt and water, Burning of wood, Cutting a piece of paper

Back

Burning of wood

Front

What is a physical change?

Back

A physical change is a change in the form or state of matter without any change in its chemical composition.

Front

True or False: According to the law of conservation of mass, mass can be created or destroyed during a chemical reaction.

Back

False

Front

What happens to the mass of a substance during a physical change?

Back

The mass of a substance remains constant.

Front

Example of a physical change.

Back

Melting ice into water.

Front

What is the difference between a chemical change and a physical change?

Back

A chemical change involves a chemical reaction that results in the formation of new substances with different properties, while a physical change only involves a change in the physical properties of a substance.

Front

A 500-gram block of solid cheese is melted in a pot. What is the most likely mass of the cheese after it is melted?

Back

500 grams, because the cheese does not gain or lose mass just because it was melted

Front

Jamie weighs a glass of water and observes its weight to be 12 ounces. Jamie then adds 6 ice cubes to the glass of water. Each ice cube weighs one ounce. After all of the ice cubes have melted, what will be the approximate weight of the glass of water?

Back

18 ounces

Front

For the equation:
2H₂ +  O₂ --> 2H₂O
How much H₂O will be produced if we react 4g of H₂ and 32g of O₂?

Back

36g