Front

What is a chemical change?

Back

A chemical change is a process where substances combine or break apart to form new substances with different properties.

Front

What is a physical change?

Back

A physical change is a change that affects one or more physical properties of a substance without altering its chemical composition.

Front

What happens during fireworks exploding?

Back

Fireworks exploding is an example of a chemical change because new substances are formed during the reaction.

Front

What is rusting?

Back

Rusting is a chemical change that occurs when iron reacts with oxygen and moisture, forming iron oxide (rust).

Front

What does it mean for a chemical equation to be balanced?

Back

A balanced chemical equation has the same number of each type of atom on both sides of the equation, indicating that mass is conserved.

Front

Is the equation Al + O₂ --> 2Al₂O₃ balanced?

Back

No, the equation is not balanced.

Front

What are exothermic reactions?

Back

Exothermic reactions are chemical reactions that release heat, making the surroundings feel hot.

Front

What are endothermic reactions?

Back

Endothermic reactions are chemical reactions that absorb heat, making the surroundings feel cold.

Front

Is the equation 2C₂H₂ + 5O₂ --> 4CO₂ + 2H₂O balanced?

Back

Yes, the equation is balanced.

Front

What is the law of conservation of mass?

Back

The law of conservation of mass states that mass cannot be created or destroyed in a chemical reaction.