Chemistry 9701 · AS & A Level · Chemistry of transition elements

Chemistry of transition elements — practice question

(a(i))[1]

Define what is meant by transition element.

(a(ii))[1]

State how the melting point and density of iron compare with those of calcium.

(b(i))[2]

Define what is meant by standard cell potential, $E^{\circ}_{\text{cell}}$.

(b(ii))[3]

Draw a fully labelled diagram of the apparatus used to measure the cell potential of a cell made from a Cu(II)/Cu electrode and an Fe(III)/Fe(II) electrode. Include all required reactants.

(c(i))[2]

Use equations to show the catalytic function of $\text{Fe}^{3+}$ in the reaction between $\text{S}_2\text{O}_8^{2-}(aq)$ and $\text{I}^-(aq)$.

(c(ii))[2]

$\text{Fe}^{3+}(aq)$ can oxidise $\text{I}^-(aq)$, whereas $[\text{Fe(CN)}_6]^{3-}(aq)$ cannot oxidise $\text{I}^-(aq)$. Use $E^{\circ}$ values to explain these observations.

(d(i))[1]

Suggest why this reaction proceeds slowly without the $\text{Fe}^{3+}$ catalyst.

(d(ii))[1]

Use the overall equation to work out the half-equation for the oxidation of tartrate ions, $\text{C}_4\text{H}_4\text{O}_6^{2-}$, to carbon dioxide, $\text{CO}_2$, and methanoate ions, $\text{HCO}_2^-$. $\text{C}_4\text{H}_4\text{O}_6^{2-} + \ldots \rightleftharpoons \ldots$

(e(i))[3]

Complete the table to show the structures of the organic products formed when tartaric acid reacts separately with each reagent. Identify the type of reaction in each case.

(e(ii))[1]

Tartaric acid reacts with the amine 1-phenylethylamine, $\text{C}_6\text{H}_5\text{CH}(\text{NH}_2)\text{CH}_3$, to produce an ionic salt. Draw the structure of the salt formed in this reaction. Include the charges on the ions.

Worked solution & mark scheme

This 17-mark question has a full step-by-step worked solution and mark scheme. One marking point: forms stable ions/oxidation states and possesses a partially filled $d$ subshell

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI