In the industrial extraction of titanium, titanium(IV) oxide (TiO2\text{TiO}_2TiO2) is first converted to titanium(IV) chloride (TiCl4\text{TiCl}_4TiCl4). The purified TiCl4\text{TiCl}_4TiCl4 is then reduced using liquid magnesium at high temperatures in a batch reactor:
TiCl4(g)+2Mg(l)→Ti(s)+2MgCl2(l) \text{TiCl}_4(\text{g}) + 2\text{Mg}(\text{l}) \rightarrow \text{Ti}(\text{s}) + 2\text{MgCl}_2(\text{l}) TiCl4(g)+2Mg(l)→Ti(s)+2MgCl2(l)Which statement correctly describes the redox behavior of the species involved and the purpose of using an inert argon atmosphere during this process?
Magnesium acts as the oxidizing agent and is reduced, while the argon atmosphere prevents the highly reactive magnesium and titanium metals from reacting with oxygen and nitrogen in the air.
The titanium in TiCl4\text{TiCl}_4TiCl4 is reduced because its oxidation state decreases from +4+4+4 to 000, and the argon atmosphere is required because both magnesium and titanium react readily with oxygen and nitrogen at high temperatures.
The titanium in TiCl4\text{TiCl}_4TiCl4 is oxidized because its oxidation state increases from +2+2+2 to +4+4+4, and the argon atmosphere acts as a homogeneous catalyst to increase the rate of titanium deposition.
Magnesium acts as the reducing agent and is reduced, while the argon atmosphere is required to prevent the gaseous TiCl4\text{TiCl}_4TiCl4 from undergoing thermal decomposition.
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