Balancing Equations

L.G.

  • Be able to write chemical worked equations

  • Understand the law of conservation of mass


Chemical Reaction

Reactants (Substance you start with) → Products (new substance at the end)


Signs of a chemical reactions

  1. Colour change

  2. Gases formed

  3. Change in energy (heat or light)

  4. Precipitate formed


Eg.

Carbon + Oxygen → Carbon dioxide

Hydrogen + Oxygen → Water

Sodium + Chloride → Salt


Catalyst → A substance that speeds up a reaction but is not used up in the reaction.


Law of Conservation of Mass

  • Mass is neither created nor destroyed in a chemical reaction

  • The total mass of the products must always equal the total mass of the reactants

  • The total number of atoms on one side of the equation MUST equal the total number of atoms on the other side