Chemistry 9701 · AS & A Level · Hydroxy compounds

Hydroxy compounds — practice question

But-2-ene is oxidised by $\text{KMnO}_4$ to give the organic compound $\text{Y}$. $\text{Y}$ does not react with $\text{Na}_2\text{CO}_3$. When an excess of $\text{Na}$ is added to $\text{Y}$, a gas is given off.
(a(i))[1]

Describe the conditions of the $\text{KMnO}_4$ used to convert but-2-ene into $\text{Y}$.

(a(ii))[3]

At room conditions, $24.0\,\text{cm}^3$ of gas is released when an excess of $\text{Na}$ is added to $0.001\,\text{mol}$ of $\text{Y}$. Assume that under room conditions $1\,\text{mol}$ of gas occupies $24.0\,\text{dm}^3$.\n\nDeduce a possible structure of $\text{Y}$. Explain your answer.

(b(i))[1]

Deduce the number of carbon atoms in a molecule of $\text{Z}$ from Fig. 5.1. Show your working.

(b(ii))[1]

Deduce which halogen is present in $\text{Z}$ from Fig. 5.1. Explain your answer.

(b(iii))[3]

Further peaks occur at $m/e = 29$ and $m/e = 49$.\n\nSuggest the formulae of these fragments. Deduce the name of $\text{Z}$.\n\n$m/e = 29$\n\n$m/e = 49$\n\nname of $\text{Z}$

(ii)[1]

Deduce which halogen is present in $Z$ from Fig. 5.1. Explain your answer.

(iii)[3]

Further peaks occur at $m/e = 29$ and $m/e = 49$.\n\nSuggest the formulae of these fragments. Deduce the name of $Z$.\n\n$m/e = 29$\n\n$m/e = 49$\n\nname of $Z$

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