GCSE Chemistry Key Stage 4 Organic chemistry Reactions

GCSE Chemistry - Key Stage 4 Organic chemistry Reactions of alkenes Dr Patel 1

Source of image: Oak 2

Introducing alkenes 3 Alkene name Molecular formula Ethene C 2 H 4 Propene C 3 H 6 Butene C 4 H 8 Pentene C 5 H 10 Hexene C 6 H 12

Independent practice 1. What is the functional group found in alkenes? 2. What is a homologous series? 3. Name the first 4 alkenes. 4. What is the general formula for an alkene? 5. What do the names of all alkenes end in? Challenge: An alkene has 10 carbons. State it’s molecular formula and name it. 4

Drawing alkenes Rules 1. Write out the number of carbons you need. 2. Add one double bond (between 2 Cs). 3. Then complete the other bonds, making sure all Cs have 4 bonds coming off them 4. Add all Hs. H H 5 C C H H C C H

Independent practice Draw the following alkenes onto your white boards: Pentene C 5 H 8 Hexene C 6 H 12 6

Independent practice Copy and complete the reaction below to show the addition of hydrogen to ethene: H H H C C H + H Challenge: Name the product 7 H

Independent practice Copy and complete the reaction below to show the addition of chlorine to ethene: H H H C C H + Cl Challenge: Name the product 8 Cl

Independent practice Copy and complete the reaction below to show the addition of water to ethene: H H H C C H + O H Challenge: Name the product 9 H

Independent practice Balance the equation in questions 1, 2 and 3. 1. CH 4 + O 2 → CO 2 + H 2 O 2. C 2 H 6 + O 2 → CO 2 + H 2 O 3. C 2 H 4 + O 2 → C + CO + H 2 O 4. Name the reactants and products for reactions 1, 2 and 3. 5. What is the difference between reaction 2 and 3? 6. What difference would you SEE in reaction 2? 10