In Stage 2 of a reaction, 40 kg of titanium chloride was added to 20 kg of sodium. The equation for the reaction is: TiCl4 + 4Na -> Ti +4NaCl Relative atomic masses (Ar): Na = 23 Cl = 35.5 Ti = 48 Explain why titanium chloride is the limiting reactant.

To calculate which of titanium chloride or sodium is limiting, convert both into mol so they are directly comparable. You cannot compare in masses because in equations there is a conservation of moles and not mass. Mol = Mass/Mr (Remember most of the time information in the question is valuable).Mass in this equation is in g, so the weight of TiCl4 = 40,000 and weight of sodium = 20,000Mr of TiCL4 = 48 + (35.5 x 4) = 190Mol of TiCl4 = 40,000/190 = 210.52 = 211 mol (round to 3s.f. if not specified)Mol of Na = 20,000/23 = 869.56 = 870 mol1TiCl4 for every 4Na870/4 = 217.5 (for 1 Na)Therefore: TiCl4 is in excess. 211mol compared to 217.5 mol