`Fe^(3+)overset(SCN^(-)(excess))to "blood red"(A)overset(F^(-)(excess))to"colourless"(B)`Identify A and B
(a) Write IUPAC name of A and B
(b) Find out spin only magnetic moment of B.

Explanation

To solve the problem step by step, we will identify the compounds A and B, write their IUPAC names, and calculate the spin-only magnetic moment of compound B.

### Step 1: Identify Compound A
When Fe³⁺ reacts with SCN⁻ in excess, it forms a blood-red colored complex. This complex is known as ferric thiocyanate.

**Compound A:** Fe(SCN)₃
**Color:** Blood red

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