MCQ
Which of the following complex has zero magnetic moment (spin only)?
- A$[Ni(NH_3)_6]Cl_2$
- B$Na_3[FeF_6 ]$
- C$[Cr(H_2O)_6]SO_4$
- ✓$K_4[Fe(CN)_6 ]$
$N{a_3}[Fe{F_6}]$ $\to $ $s{p^3}{d^2}$ hybridisation $\to $ $3$ unpaired electrons
$[Cr{({H_2}O)_6}]S{O_4}$ $\to $ ${d^2}s{p^3}$ hybridisation $\to $ $3$ unpaired electrons
${K_4}[Fe{(CN)_6}]$ $\to $ ${d^2}s{p^3}$ hybridisation $\to $ No unpaired electrons
Zero magnetic moment means all the electrons paired.
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| $S \,No.$ | Time $(s)$ | Total pressure $(atm)$ |
| $1$ | $0$ | $0.5$ |
| $2$ | $100$ | $0.6$ |
Calculate the rate constant
Reason : Zinc is a powerful reducing agent than copper.
$\Delta {H_{{\rm{System}}}} = 2000\ kJ/mol$
$T = 400\ K$
Find out value of $\Delta {S_{{\rm{System}}}}$..........$ kJ/mol-K$