Complete the statements in COLUMN A with the options in COLUMN B. Write only A or B next to the question numbers (1.1.1 to 1.1.7) in the ANSWER BOOK, for example 1.1.8. B.

Step 1: Primary test for test tube A with dilute aqueous NaOH.
White precipitate formed, insoluble in excess NaOH.
$Pb^{2+} + 2OH^- \to Pb(OH)_2 \downarrow$
No dissolution on adding excess $NaOH$.
Inference: $Pb^{2+}$, $Hg_2^{2+}$, $Bi^{3+}$, $Cu^{2+}$, $Cd^{2+}$, $Fe^{3+}$, $Al^{3+}$, $Cr^{3+}$, $Zn^{2+}$ (but pattern matches group II).

Step 2: Test with dilute aqueous $NH_4OH$.
White precipitate, insoluble in excess.
$Pb(OH)_2 insoluble in NH_4OH$
Confirms group II cation.

Step 3: Secondary test - $H_2S$ in acidic medium.
Black precipitate.
$Pb^{2+} + H_2S \to PbS \downarrow + 2H^+$
Inference: $Pb^{2+}$.

Cation in A: $Pb^{2+}$

Step 4: Primary test for test tube B with dilute aqueous NaOH.
Blue precipitate formed, insoluble in excess NaOH.
$Cu^{2+} + 2OH^- \to Cu(OH)_2 \downarrow$
No dissolution on adding excess $NaOH$.

Step 5: Test with dilute aqueous $NH_4OH$.
Precipitate dissolves in excess to give deep blue solution.
$Cu(OH)_2 + 4NH_3 \to [Cu(NH_3)_4]^{2+} + 2OH^-$
Inference: $Cu^{2+}$.

Cation in B: $Cu^{2+}$

Step 6: Primary test for test tube C with dilute aqueous NaOH.
Reddish-brown precipitate, insoluble in excess NaOH and $NH_4OH$.
$Fe^{3+} + 3OH^- \to Fe(OH)_3 \downarrow$
Insoluble in excess reagents.

Step 7: Confirmatory test - potassium ferrocyanide.
Prussian blue precipitate.
$3K^+ + [Fe(CN)_6]^{4-} + Fe^{3+} \to Fe_4[Fe(CN)_6]_3 \downarrow$
Cation in C: $Fe^{3+}$

Step 8: Primary test for test tube D with dilute aqueous NaOH.
White precipitate, soluble in excess NaOH.
$Zn^{2+} + 2OH^- \to Zn(OH)_2 \downarrow$
$Zn(OH)_2 + 2OH^- \to [Zn(OH)_4]^{2-}$

Step 9: Test with aqueous $NH_4OH$.
White precipitate dissolves in excess.
$Zn(OH)_2 + 4NH_3 \to [Zn(NH_3)_4]^{2+} + 2OH^-$
Cation in D: $Zn^{2+}$

Final answers (Q11):
A: Pb^{2+
B: Cu^{2+}
C: Fe^{3+}
D: Zn^{2+}}