Natural Chemistry

Natural Chemistry

1. Alkanes

   • Saturated hydrocarbons
     • Only one single covalent bond
   • C(n)H(2n+1)
   • Most hydrocarbons in crude oil are alkanes
     • Give out large amounts of energy when burnt
   • The bigger the molecule, the higher the boiling/melting point
     • And so the less flammable they become
   • Very flammable
   • The bonds between carbon and hydrogen atoms don't break

2. Empirical formula

   • Worked Example
     • Benzene has the molecular formula of C6H6, what is its empirical formula? The ratio of carbon to hydrogen is 1:1, so the empirical formula would be CH.
   • Good for representing ionic compounds

3. Alkenes

   • C2H2
   • Unsaturated hydrocarbons
     • The molecules have double covalent bonds
     • More reactive than alkanes
   • Very flammable
     • Burn in combustion reactions to produce carbon dioxide and water