Post on 09-Jul-2015
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+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