Chemistry 9701 · AS & A Level · States of matter

States of matter — practice question

(a(i))[1]

Define transition element.

(a(ii))[1]

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

(b(i))[2]

Define standard cell potential, $E^{\circ}_{\text{cell}}$.

(b(ii))[3]

Draw a fully labelled diagram of the equipment that may be used to measure the cell potential of a cell made from a $\text{Cu(II)}/\text{Cu}$ electrode and an $\text{Fe(III)}/\text{Fe(II)}$ electrode. Include all necessary reactants.

(c(i))[2]

The reaction between $\text{S}_2\text{O}_8^{2-}(aq)$ and $\text{I}^-(aq)$ is sped up by adding a few drops of $\text{Fe}^{3+}(aq)$. Use equations to demonstrate the catalytic function of $\text{Fe}^{3+}$ in this reaction.

(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 account for these observations.

(d(i))[1]

When aqueous solutions of $\text{S}_2\text{O}_8^{2-}$ and tartrate ions are mixed the reaction proceeds very slowly. However, this reaction proceeds quickly in the presence of an $\text{Fe}^{3+}(aq)$ catalyst. Suggest why this reaction is slow 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, $\text{HCO}_2^-$.

(e(i))[3]

Complete the table below 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, $\text{C}_6\text{H}_5\text{CH(NH}_2)\text{CH}_3$, 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 / compounds and contains partially filled d orbitals

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