Chapter 4 · Chemistry
Carbon and its Compounds
Catenation and tetravalency let carbon form millions of compounds. The live module builds any straight-chain compound from real valency rules and derives its molecular formula and IUPAC name.
Carbon Compound Builder
Choose a chain length and homologous series — IUPAC name, molecular formula and structure are derived from the general formula rules.
- IUPAC name
- propane
- Molecular formula
- C3H8
- Approx. molar mass
- 44.0 u
- Functional group
- none
- C–C σ bonds
- 2
- Extra π bonds
- 0
- C–H / heteroatom bonds
- 8
- Total bonds
- 10
- Homologous series rule
- Each next member differs by CH2 (14 u) — the homologous series difference.
Formula sheet
Alkane
CₙH₂ₙ₊₂
Saturated; only single bonds. Methane CH₄, ethane C₂H₆.
Alkene
CₙH₂ₙ
One C=C double bond. Ethene C₂H₄.
Alkyne
CₙH₂ₙ₋₂
One C≡C triple bond. Ethyne C₂H₂.
Homologous difference
−CH₂− (14 u)
Successive members differ by one CH₂ unit and 14 u of mass.
Esterification
CH₃COOH + C₂H₅OH ⇌(conc. H₂SO₄) CH₃COOC₂H₅ + H₂O
Acid + alcohol gives a sweet-smelling ester.
Saponification
Ester + NaOH → Sodium salt of acid + Alcohol
The reaction used to make soap.