Match the test in Column I with the observation in Column II. Column I: (P) Cu^2+ + K4[Fe(CN)6]; (Q) Sn^2+ + excess HgCl2; (R) Cd^2+ + H2S (dil. acid); (S) Bi(OH)3 + sodium stannite. Column II: (1) yellow precipitate; (2) black precipitate; (3) chocolate-brown precipitate; (4) white silky precipitate.

JEE Main levelSingle correct optionDifficulty 2 of 3qc176

Match the test in Column I with the observation in Column II. Column I: (P) $Cu X^{2 +}$ + $K X_{4} [Fe (CN) X_{6}]$ ; (Q) $Sn X^{2 +}$ + excess $HgCl X_{2}$ ; (R) $Cd X^{2 +}$ + $H X_{2} S$ (dil. acid); (S) $Bi (OH) X_{3}$ + sodium stannite. Column II: (1) yellow precipitate; (2) black precipitate; (3) chocolate-brown precipitate; (4) white silky precipitate.

Cu gives chocolate-brown

Cu X_{2} [Fe (CN) X_{6}]

(3); Sn(II) reduces

HgCl X_{2}

to white silky

Hg X_{2} Cl X_{2}

(4); Cd gives yellow CdS (1); stannite reduces Bi(III) to black Bi (2). So P-3, Q-4, R-1, S-2.