JEE Advanced 2020 Full Test 4 Paper 2

Treatment of NaCl with acidified solution of (X) forms a red vapour( Y ). Treatment of (Y) with aqueous NaOH forms a yellow solution( Z ). Pb(CH3COO)2 gives a yellow precipitate when treated with solution of (Z). What is the molar mass of (Y) in gmol−1 unit?
[At. Mass of Cr=51.9]