Calculate the mass of impure iron that was used in the experiment.
What does the term an excess of dilute sulfuric acid mean?
What safety precaution ought to be used when heating the beaker? Explain your answer.
What else could the student do to make the reaction in the beaker go faster?
Suggest a way of separating the insoluble impurities from the aqueous solution.
Suggest how the student should make sure that all of the solution is moved into the volumetric flask.
Use the diagrams to complete the table and calculate the average volume of Q.
Give two reasons why the student does three titrations using $25.0\,\text{cm}^3$ of P in each, rather than carrying out one titration using $250\,\text{cm}^3$ of P.
Calculate the number of moles of potassium manganate(VII) in the average volume of $0.0200\,\text{mol dm}^{-3}$ aqueous potassium manganate(VII).
One mole of potassium manganate(VII) reacts with five moles of $\text{Fe}^{2+}$. Calculate the number of moles of $\text{Fe}^{2+}$ in $25.0\,\text{cm}^3$ of P.
Calculate the number of moles of $\text{Fe}^{2+}$ in $250\,\text{cm}^3$ of P.
Calculate the mass of iron in $250\,\text{cm}^3$ of P. $[A_r(\text{Fe}) = 56]$
Using your answers to (a) and (h), calculate the percentage by mass of iron in the impure iron.