S2 Chemistry Equations

Word Equations Learning Intention We are learning to write word equations

Word Equations All chemical reactions can be described using a word equation eg reactants products (what you start with) (what you end up with)

Word Equations eg magnesium + oxygen magnesium oxide

Word Equations Write a word equation for the following reaction

Word Equations Write a word equation for the following reaction Carbon dioxide is formed when carbon burns in oxygen.

Word Equations Write a word equation for the following reaction Carbon dioxide is formed when carbon burns in oxygen. carbon + oxygen carbon dioxide

Formula Equations Learning Intention We are learning to write formula equations

Formula Equations Instead of using words, the formula for the reactants and products can be used instead. This is called a formula equation. carbon + oxygen carbon dioxide

Formula Equations Instead of using words, the formula for the reactants and products can be used instead. This is called a formula equation. carbon + oxygen carbon dioxide C + O2 CO2

Formula Equations Eg hydrogen + oxygen hydrogen oxide

Formula Equations Eg hydrogen + oxygen hydrogen oxide H2 + O2 H2O

Diatomic Elements Certain elements always go around in pairs. These are the diatomic elements.

Diatomic Elements Certain elements always go around in pairs. These are the diatomic elements. H2, O2, N2, F2, Cl2, Br2, I2

Diatomic Elements Certain elements always go around in pairs. These are the diatomic elements. H2, O2, N2, F2, Cl2, Br2, I2 In formula equations they must always be written as pairs.

Balancing Equations A balanced equation is when the number of each element on the product side equals the number of each element on the reactant side.

Balancing Equations Eg C + O2 CO2 This is balanced.

Balancing Equations Eg H2 + O2 H2O

Balancing Equations Eg H2 + O2 H2O This is not balanced.

carbon + chlorine C + Cl2 CCl4

carbon + chlorine C + Cl2 CCl4 C C Cl Cl

carbon + chlorine C + Cl2 CCl4 C 1 C 1 Cl 2 Cl 4

carbon + chlorine C + 2Cl2 CCl4 C 1 C 1 Cl 4 Cl 4

Combustion of Methane CH4 + O2 CO2 + H2O C C H H O O

Combustion of Methane CH4 + O2 CO2 + H2O C 1 C 1 H 4 H 2 O 2 O 3

Combustion of Methane CH4 + O2 CO2 + 2H2O C 1 C 1 H 4 H 4 O 2 O 4

Combustion of Methane CH4 + 2O2 CO2 + 2H2O C 1 C 1 H 4 H 4 O 4 O 4

Calculations from Equations C + O2 CO2

Calculations from Equations C + O2 CO2 12g

Calculations from Equations C + O2 CO2 12g 32g

Calculatios from Equations C + O2 CO2 12g 32g 44g

Calculations from Equations C + O2 CO2 12g 32g 44g 6g 16g 22g

Calculations from Equations C + O2 CO2 12g 32g 44g 6g 16g 22g 1.2g 3.2g 4.4g