A mixture of PCl₅ (12.41 g) and excess NH₄Cl was heated at 145°C for 6 hours. The two reacted in equimolar amounts and evolved 5.14 L of HCl (at STP). Three substances (A, B, and C) were isolated from the reaction mixture. The three substances had the same elemental composition but differed in their molar mass. Substance A had a molar mass of 347.7 g/mol and B had a molar mass of 463.5 g/mol. Give the empirical and molecular formulas for A and B and draw a reasonable Lewis structure for A.