Problems and exercisesPhysical Properties
1. Melting points of the but-2-enes
Why does trans- or E-but-2-ene melt at a higher temperature than its cis or Z isomer?
| Alkene | Formula | b.p. (°C) | m.p. (°C) |
|---|---|---|---|
| cis-But-2-ene | CH3CH=CHCH3 (Z) | 4 | −139 |
| trans-But-2-ene | CH3CH=CHCH3 (E) | 1 | −105 |
2. Order by boiling point
Order from lowest to highest boiling point: pent-1-ene, hex-1-ene, 2-methylbut-1-ene and hept-1-ene.
3. Solubility
Is hex-1-ene soluble in water? And in hexane? Does it float or sink in water?