Question

why was it necessary to wash the crude cyclohexene product (part A) with aqueous sodium carbonate? (Give an equation)

Answer 1

Answer:- Generally, cyclohexene is prepared from the dehydration of cyclohexanol using acid (H_{3​​​​​​​}PO₄ or H​​​​​​​_{2​​​​​​​}SO₄ ) as a catalyst. The crude cyclohexene (alkene) formed contains many impurities like unreacted alcohol , water, and traces of acid. To remove or to neutralize the acidic impurities, generally the product (cyclohexene) is washed with sodium carbonate solution. After, treatment with aqueous sodium carbonate , the product get washed with water to remove excess sodium carbonate, unreacted alcohol and other water-soluble impurities.

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H​​​​​​​​​​​​​​_{2​​​​​​​}SO₄ (impurity) + Na₂CO_{3 (aq)}    Na₂SO_{4 (aq)} + H₂O _(l) + CO_2(g)

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