Which of the following statements is/are not true?

Options

A. `Fe^(2+)` (aq) gives brown colour with `NH_(4)CNS`.
B. `Fe^(2+)`(aq) gives blue colour or precipitate with `K_(3)Fe(CN)_(6)`.
C. `Fe^(3+)`(aq) yields brown colour with `K_(3)Fe(CN)_(6)`.
D. All of the above.

Explanation

To determine which of the statements is/are not true regarding the reactions of iron ions with various reagents, we will analyze each option step by step.

### Step 1: Analyze Option 1
**Statement**: Fe²⁺ aqueous gives a brown color with NH₄CNS.

**Analysis**:
- When Fe²⁺ reacts with NH₄CNS (ammonium thiocyanate), it forms a complex ion, [Fe(CNS)₂]⁻.
- The expected color of this complex is red, not brown.
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