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Read the passage and answer the questions.
‘In 1915, a senior lecturer in Biochemistry at the University of Manchester named Dr. Chaim…
‘In 1915, a senior lecturer in Biochemistry at the University of Manchester named Dr. Chaim Weizmann invented a fermented process that converts starch into acetone and butanol by using Clostridium acetobutylicum. Acetone was the key component in the production of the smokeless gunpowder (cordite) used by the Allies in World War I. Acetone was previously made from calcium acetate imported from Germany, since Allies were in war with Germany, this was no longer possible.’
Source: https://www.weizmann.ac.il/WeizmannCompass/sections/people-behind-the-science/chaim-weizmann%E2%80%99s-acetone-patent-turns-100
(a)[2.0]
How will you prepare acetone from calcium acetate?
(b)[2.0]
If butan-2-ol is oxidised by $\text{K}_2\text{Cr}_2\text{O}_7$, which ketone will be produced? Give the balanced chemical reaction.
(c)[1.0]
How would you obtain acetone from acetyl chloride?
Answer
Answer (a)
Official answer keyBy dry distillation of calcium acetate, we can obtain acetone
$\mathrm{Ca(CH_3COO)_2 \xrightarrow{heat} CH_3COCH_3 + CaCO_3}$
Answer (b)
Official answer key$\mathrm{CH_3CH(OH)CH_2CH_3 + [O] \rightarrow CH_3COCH_2CH_3 + H_2O}$
Answer (c)
Official answer key$\mathrm{2CH_3COCl + (CH_3)_2Cd \rightarrow 2CH_3COCH_3 + CdCl_2}$
From ISC 2025 Practice Chemistry, question 96.