Match the hexaaqua ions in List I with their colours in List II. List I: (P) [Cu(H2O)6]^2+, (Q) [Ni(H2O)6]^2+, (R) [Co(H2O)6]^2+, (S) [Cr(H2O)6]^3+. List II: (1) violet, (2) pink, (3) green, (4) blue.

JEE Main levelSingle correct optionDifficulty 2 of 3df137

Match the hexaaqua ions in List I with their colours in List II. List I: (P) $[Cu (H X_{2} O) X_{6}] X^{2 +}$ , (Q) $[Ni (H X_{2} O) X_{6}] X^{2 +}$ , (R) $[Co (H X_{2} O) X_{6}] X^{2 +}$ , (S) $[Cr (H X_{2} O) X_{6}] X^{3 +}$ . List II: (1) violet, (2) pink, (3) green, (4) blue.

The aqua ions are blue for

Cu X^{2 +}

, green for

Ni X^{2 +}

, pink for

Co X^{2 +}

and violet for

Cr X^{3 +}

. This gives P-4, Q-3, R-2, S-1.