Chemistry - Complete d-block Question with Solution | TestHub
In certain oxidations catalyzed by using peroxodisulfate ion , a black solid A of composition AgO can be isolated. Single - crystal X-ray studies reveal that the lattice of 'A' contains two crystallographically non-equivalent silver sites ( and ) in equal proportion.
Here ⇒ Ag1 shows coordination number 2,
⇒ Ag2 shows coordination number 4,
⇒ All oxygen atoms are crystallographically equivalent. Let
• X = number of unpaired electrons per atom.
• Y = number of unpaired electrons per atom.
• Z = moles of required to convert 10 moles of Ag+ completely into solid 'A' .
Calculate the value of (X + Y + Z).
Answer:
Solution:
• Ag in AgO exists in mixed oxidation states +1 and +3 (in equal amount).
• Ag(I) → d¹⁰ → 0 unpaired electrons (hence ).
• Ag(III) → d⁸ (square planar / low spin due to coordination with O²⁻) → 0 unpaired electrons (hence ).
• For every 2 Ag⁺ oxidized to AgO (Ag⁺ + Ag³⁺), 1 mole of S₂O₈²⁻ is required.
• To convert 10 moles Ag⁺ → 5 moles Ag₂O₂ equivalent → requires 5 moles of S₂O₈²⁻ (hence ). So, .
