Y is formed from X in a single-step reaction, as shown in Fig. 5.1. [Figure 5.1]

1. (a)Deduce the empirical formula of Y.[1]
2. (b)The formation of Y from X requires the addition of a suitable reducing agent.
3. (b)(i)Construct an equation using molecular formulae and [H] for the reaction in Fig. 5.1. Use [H] to represent one atom of hydrogen from the reducing agent.[1]
4. (b)(ii)Identify a suitable non-gaseous reducing agent for the formation of Y from X.[1]
5. (c)Complete Table 5.1 to show the number of sp² and sp³ hybridised carbon atoms in a molecule of X. Table 5.1 type of hybridisation sp² sp³ number of carbon atoms in X[2]
6. (d)Complete Table 5.2 with the expected observations that occur when the reagents shown are added to separate solutions of X and Y. Do not refer to temperature changes in your answer. Table 5.2 reagent observation on addition to X observation on addition to Y aqueous sodium carbonate 2,4-dinitrophenylhydrazine (2,4-DNPH reagent) alkaline aqueous iodine[3]

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