artefact 2

+Berylium cation with a charge of 2 is bonded with fluoride anion with a charge of 1.

+Aluminium cation with a charge of three is bonded to sulfide anion with a charge of 2.

+ Step 1 – Identify the reactants and the products.

+ Think about making a cake. The ingredients are the reactants and the cake is the product

+ Step 2 – Write a word equation.

+ Reactants are on one side and products on the other.

+ Reactant + Reactant Product + Product

+ Step 3 – Write an unbalanced chemical equation.

+ Replace the names of each substance with their chemical names. (chemical symbols)

+ Step 4 – Balance the equation.

+ When there is an uneven number of atoms on each side of the equation.

+ You cannot change the make up of the substances only increase the amount of the whole substance.

+H2 + O2 H2O

+H2 + Cl2 HCl

+H2 + N2 NH3

+What are the signs that a chemical reaction has taken place.

+ Energy takes the form of heat or light.

+ When energy is released during a chemical reaction it is know as an exothermic reaction.

+ When a reaction takes in energy it is known as an endothermic reaction.

+ Absorbs energy from their surroundings, cooling them down.

+ If the reaction took place in a solution of water you would be able to measure a decrease in temperature.

+ Release energy as heat or light.

+ Combustion

+ Corrosion

+ Respiration

+2Ca +O2 CaO

+C3H8 + 4H2O + CO2

+2Li + H2O LiOH + H2