Lawrie Ryan and Roger Norris Solutions for Chapter: Carbonyl Compounds, Exercise 11: EXAM-STYLE QUESTIONS

Draw the skeletal formulae of :

pentan-$3$-one

Draw the skeletal formulae of :

pentanal

Describe the results you would expect to see if pentan-$3$-one and pentanal were separately treated with Tollens' reagent. Where a reaction takes place, name the organic product and name the type of reaction that takes place. 
 

Ethanol can be made from ethanal using sodium tetrahydridoborate (III) as a reducing agent. Give the formula of sodium tetrahydridoborate (III). 

$$\begin{gathered} \mathrm{A}: {\mathrm{NaBH}}_2 \\ \mathrm{B}: {\mathrm{NaBH}}_4 \\ \mathrm{C}: {\mathrm{NaBH}}_3 \end{gathered}$$

(Enter your correct answer as $\mathrm{A}, \mathrm{B} \mathrm{or} \mathrm{C}$)

Ethanol can be made from ethanal using sodium tetrahydridoborate (III) as a reducing agent. The reaction mechanism proceeds in a similar way to the steps in the reaction of ethanal with $\mathrm{HCN}$, but the initial attack is by the ${\mathrm{H}}^{+}$ion instead of the ${\mathrm{CN}}^{-}$ion. The intermediate then gains an ${\mathrm{H}}^{+}$ion from a water molecule to form the product, ethanol.

Using your knowledge of the reaction between ethanal and $\mathrm{HCN}$, suggest the name of the mechanism to reduce ethanal. Then describe the mechanism as fully as you can, using curly arrows to show the movement of electron pairs. 

Ethene can be obtained by cracking large hydrocarbons found in crude oil. Suggest how ethene can be converted into ethylamine, stating the reagents and conditions needed.

Ethene can be obtained by cracking large hydrocarbons found in crude oil. Suggest how ethene can be converted into ethanal, stating the reagents and conditions needed.

Ethene can be obtained by cracking large hydrocarbons found in crude oil. Suggest how ethene can be converted into propanoic acid, stating the reagents and conditions needed.