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Chemical reactionsWrite the chemical name for...Berylium cation with a charge of 2 is bonded with fluoride anion with a charge of 1.Write the chemical name for...Aluminium cation with a charge of three is bonded to sulfide anion with a charge of 2.Writing chemical equations.Step 1 Identify the reactants and the products.
Think about making a cake. The ingredients are the reactants and the cake is the productWriting chemical equations.Step 2 Write a word equation.
Reactants are on one side and products on the other.
Reactant + Reactant Product + ProductWriting chemical equations.Step 3 Write an unbalanced chemical equation.
Replace the names of each substance with their chemical names. (chemical symbols)Writing chemical equations.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.
Balance these EquationsH2 + O2 H2O
H2 + Cl2 HCl
H2 + N2 NH3RememberWhat are the signs that a chemical reaction has taken place.Release of energyEnergy 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.Endothermic reactionAbsorbs 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.
Exothermic ReactionRelease energy as heat or light.
Balance these equations2Ca +O2 CaO
C3H8 + 4H2O + CO2
2Li + H2O LiOH + H2