chemistry - separate chemistry 2: hydrocarbons (9.10 - 9.16)

9.10 methane - formula

CH₄

9.10 methane - structure

9.10 ethane - formula

C₂H₆

9.10 ethane - structure

9.10 propane - formula

C₃H₈

9.10 propane - structure

9.10 butane - formula

C₄H₁₀

9.10 butane - structure

alkane general formula

C_nH_2n+2

alkene general formula

H_nC_2n

9.11 why are alkanes saturated hydrocarbons?

carbon atoms joined by single covalent bonds (C-C)

9.12 ethene - formula

C₂H₄

9.12 ethene - structure

9.12 propene - formula

C₃H₆

9.12 propene - structure

9.12 butene - formula

C₄H₈

9.12 but-1-ene - structure

9.12 but-2-ene - structure

9.13 why are alkenes unsaturated hydrocarbons?

contain functional group C=C (carbon-carbon double bond)

9.14 ethene + bromine →

1,2-dibromoethane

9.14 ethene + bromine - structures of reactants & products

9.14 ethene + bromine - other alkenes

1,2-dibromoethane:

• “di”: means “two”

• “1,2”: 2 bromine atoms attached to diff. carbon atoms

  • if attached to same carbon atom - “1,1-dibromoethane”

9.15 bromine water - distinguish between alkanes & alkenes

bromine water = orange-brown

bromine + alkene: C=C double bond reacts with bromine → bromine removed from solution → forms colourless product

bromine + alkane: no decolourisation - remains brown

9.16 complete combustion of alkanes & alkenes

CO₂ + water produced

hydrocarbons oxidised