Formulas and equations

Question 1

What happens to the atoms in a chemical reaction?

Answer 1

• No new atoms are ever created or destroyed in a chemical reaction
• Total mass of reactants = total mass of products

Question 2

What does a formula show?

Answer 2

• Atoms/elements in a compound

Question 3

Methane (CH4) when burnt with oxygen produces carbon dioxide and water. Write a word equation:

Answer 3

Methane + Oxygen –> Carbon dioxide + Water

Question 4

Methane (CH4) when burnt with oxygen produces carbon dioxide and water. Write a balanced symbol equation:

Answer 4

CH4 + O2 –> CO2 + H2O

CH4 + 202 –> CO2 + 2H20