The sodium fusion extract gives violet color with CHCl₃ and chlorine water, indicating the presence of iodine.
In the Carius method, 0.15 g of compound Y produces 0.12 g of silver halide precipitate (AgI).
Molar mass of AgI = 108 + 127 = 235 g/mol.
Moles of AgI = 0.12 / 235 = 0.000510 mol.
Since each AgI contains one I atom, moles of I = 0.000510 mol.
Mass of I = 0.000510 × 127 = 0.0647 g.
Percentage of halogen (iodine) in compound Y
= (0.0647 / 0.15) × 100 = 43.1%, which rounds to 43% (nearest integer).