Answer: Fractional distillation.
- A Fractional distillation
- B Simple distillation
- C Steam distillation
- D Crystallisation
Correct answer: A. Fractional distillation
Explanation: When boiling points are close, a fractionating column is needed so repeated vaporisation-condensation cycles separate the components; simple distillation works only for wide boiling-point gaps.
Geometric (cis-trans) isomers of 1,2-dichloroethene differ only in the relative arrangement of groups across the rigid C=C double bond.
Concept context
General Organic Chemistry covers the rules behind all organic reactions. Covers inductive effect, resonance, hyperconjugation, types of reactions (substitution, addition, elimination), and isomerism including optical and geometric forms.
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