Vanadium is extracted from vanadium(IV) oxide in a two-stage industrial method.
Stage 1 VO2+2C+2Cl2→VCl4+2CO\quad\text{VO}_2 + 2\text{C} + 2\text{Cl}_2 \rightarrow \text{VCl}_4 + 2\text{CO}VO2+2C+2Cl2→VCl4+2CO
Stage 2 VCl4+2Mg→V+2MgCl2\quad\text{VCl}_4 + 2\text{Mg} \rightarrow \text{V} + 2\text{MgCl}_2VCl4+2Mg→V+2MgCl2
Suggest one hazard associated with Stage 1.
Suggest why the reaction in Stage 2 is carried out in an atmosphere of argon and not in air.
Vanadium(IV) chloride (VCl4\text{VCl}_4VCl4) is a liquid at room temperature. Explain why you would not expect a transition metal chloride to be a liquid at room temperature.
During Stage 2, magnesium atoms are oxidised to magnesium ions. Complete the half-equation for this oxidation. Mg→Mg2++‾\text{Mg} \rightarrow \text{Mg}^{2+} + \underline{\qquad\qquad}Mg→Mg2++
In Stage 2, 57.9 kg57.9\text{ kg}57.9 kg of vanadium(IV) chloride was added to 15.6 kg15.6\text{ kg}15.6 kg of magnesium. Relative atomic masses (ArA_rAr): Mg=24\text{Mg} = 24Mg=24, Cl=35.5\text{Cl} = 35.5Cl=35.5, V=51\text{V} = 51V=51 Explain why vanadium(IV) chloride is the limiting reactant. You must show your working.
For a Stage 2 reaction, the percentage yield of vanadium was 84.2%84.2\%84.2%. The theoretical maximum mass of vanadium produced in this batch was 21.5 kg21.5\text{ kg}21.5 kg. Calculate the actual mass of vanadium produced. Give your answer to 3 significant figures.