saturated vs unsaturated

Saturated hydrocarbon

• Only single bonds

• Maximum number of hydrogens attached

Unsaturated hydrocarbon

• Has double or triple bonds

• Fewer hydrogens attached

Why it matters (real life)

Saturated fats

• Straight chains

• Pack tightly

• Sold (butter)

Unsaturated fats

• Bent chains (kink from double bond)

• Don’t pack tightly

• Liquid (oil)

Alkenes

• Contain at least one double bond

• General formula:CnH2n

• Number in a name = position of double bond

Example

Pent-2-ene — double bond starts on carbon 2

Alkynes

• Certain triple bond

• Ending: -yne

Isomers

• Same molecular formula

• Different arrangement of atoms

• Different properties

  example

  pent-1-ene vs pent-2-ene

Key idea

• Bond type determines physical properties

• Structure affects behaviour of substances