MCQ
The formula of ferrocene is
- A${\left[ {Fe{{(CN)}_6}} \right]^{4 - }}$
- B${\left[ {Fe{{(CN)}_6}} \right]^{3 - }}$
- C$\left[ {Fe{{(CO)}_5}} \right]$
- ✓$\left[ {{{\left( {{C_5}{H_5}} \right)}_2}Fe} \right]$
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$\left\{ en = H _2 NCH _2 CH _2 NH _2\right.$; atomic numbers: $\left.Ti =22 ; Cr =24 ; Cp =27 ; Pt =78\right\}$
| List-$I$ | List-$II$ |
| $P.$ $\left[ Cr \left( NH _3\right)_4 Cl _2\right) Cl ]$ | $1.$ Paramagnetic and exhibits ionisation isomerism |
| $Q.$ $\left[ Ti \left( H _2 O \right)_5 Cl \right]\left( NO _3\right)_2$ | $2.$ Diamagentic and exhibits cis-trans isomerism |
| $R.$ $\left[ Pt ( en )\left( NH _3\right) Cl \right] NO _3$ | $3.$ Paramagentic and exhibits cis-trans isomerism |
| $S.$ $\left[ Co \left( NH _3\right)_4\left( NO _3\right)_2\right] NO _3$ | $4.$ Diamagentic and exhibits ionisation isomerism |
Codes: $ \quad P \quad Q \quad R \quad S $
Reason : $H_2N-NH_2$ is a chelating ligand.