The extraction of titanium from its ore, rutile, involves converting titanium(IV) oxide into titanium(IV) chloride before reduction.
State the purpose of each of the following steps or conditions in the industrial extraction of titanium:
(i) The conversion of titanium(IV) oxide to titanium(IV) chloride (TiCl4\text{TiCl}_4TiCl4) using carbon and chlorine.
(ii) Conducting the reduction of TiCl4\text{TiCl}_4TiCl4 with magnesium under an inert atmosphere of argon gas.
In the extraction of copper from sulfide ores, copper(I) sulfide (Cu2S\text{Cu}_2\text{S}Cu2S) is roasted in air, and silica (SiO2\text{SiO}_2SiO2) is added to remove iron(II) oxide (FeO\text{FeO}FeO) impurities. Write a balanced chemical equation for:
(i) the roasting of copper(I) sulfide in oxygen to produce copper(I) oxide and sulfur dioxide.
(ii) the reaction of iron(II) oxide with silicon dioxide to form iron(II) silicate slag (FeSiO3\text{FeSiO}_3FeSiO3).
The reduction of titanium(IV) chloride by sodium is represented by the equation:
TiCl4(g)+4Na(l)→Ti(s)+4NaCl(s) \text{TiCl}_4\text{(g)} + 4\text{Na(l)} \rightarrow \text{Ti(s)} + 4\text{NaCl(s)} TiCl4(g)+4Na(l)→Ti(s)+4NaCl(s)Explain, with reference to the oxidation states of titanium and sodium in this equation, why this is a redox reaction.
