Chemical Reactions

What type of changes the appearance change but the substance is the same.

• Physical

• Chemical

Identify the following process: We light a matchstick.

• Physical change

• Chemical change

Identify the following process: The food and the air react.

• Physical change

• Chemical change

The initial substances before occurring the chemical reaction are called...

• Reactants

• Products

The new substances after occurring the chemical reaction are called...

• Reactants

• Products

What is this ?

• a chemical reaction
• a mathematical equation
• a chemical equation

What is this ?

• a chemical reaction
• a mathematical equation
• a chemical equation

A process in which one or more substances change into others different substances.

• a chemical reaction

• a mathematical equation

• a chemical equation

The mass conservation law says

• During a chemical reaction, atoms are destroyed. The number of atoms don't remains constant throughout the reaction.

• During a chemical reaction, atoms are created. The number of atoms remains constant throughout the reaction.

• During a chemical reaction, atoms are neither created nor destroyed. The number of atoms remains constant throughout the reaction.

The airbag is a real world application of...

• synthesis reaction

• decomposition reaction

• combustion reaction

• single deplacement reaction