State how the melting point and density of iron compare with those of calcium. melting point of iron: density of iron:
Explain why these differences happen. melting point: density:
Complete the diagram by adding the parts needed to show a full circuit. Label anything you add. The diagram shows the equipment used to measure the standard electrode potential, $E^{\circ}$, of a cell made from a Cu(II)/Cu electrode and an Fe(II)/Fe electrode.
In the spaces below, identify or describe the meaning of the four letters A-D. A: B: C: D:
Use the Data Booklet to work out the $E^{\circ}$ for this cell.
State how the overall cell potential would change, if at all, as the concentration of solution C is raised. Justify your answer.
Describe how the end point of this titration would be recognised. The iron(II) complex ferrous bisglycinate hydrochloride is dissolved in dilute $\text{H}_2\text{SO}_4$ and titrated with $0.0200\,\text{mol dm}^{-3}\,\text{KMnO}_4$. The reaction equation is: $5\text{Fe}^{2+} + \text{MnO}_4^- + 8\text{H}^+ \rightarrow 5\text{Fe}^{3+} + \text{Mn}^{2+} + 4\text{H}_2\text{O}$
Calculate: • the amount of $\text{Fe}^{2+}$, in moles, in the capsule, • the iron mass in the capsule, • the molar mass of the iron(II) complex, assuming $1\,\text{mol}$ of the complex contains $1\,\text{mol}$ of iron.