MCQ
Transition elements are usually characterised by variable oxidation states but $Zn$ does not show this property because of
- Acompletion of $np-$ orbitals
- ✓completion of $(n-1)d$ orbitals
- Ccompletion of $ns-$ orbitals
- Dinert pair effect
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(Given) $\Delta H^o_f (CaCO_3,s) = -1207 \, \frac{kJ}{mol}$
$\Delta H^o_f \,(CaO,s) = -635 \,kJ/mol$
$\Delta H^o_f \,(CO_2.g) = -394 \,kJ/mol$
| Experiment No. | $\begin{array}{c}{[ A ]} \\ \left( mol dm ^{-3}\right)\end{array}$ | $\begin{array}{c}{[ B ]} \\ \left( mol dm ^{-3}\right)\end{array}$ | $\begin{array}{c}{[ C]} \\ \left( mol dm ^{-3}\right)\end{array}$ | Rate of reaction $\left( mol dm ^{-3} s ^{-1}\right)$ |
| $1$ | $0.2$ | $0.1$ | $0.1$ | $6.0 \times 10^{-5}$ |
| $2$ | $0.2$ | $0.2$ | $0.1$ | $6.0 \times 10^{-5}$ |
| $3$ | $0.2$ | $0.1$ | $0.2$ | $1.2 \times 10^{-4}$ |
| $4$ | $0.3$ | $0.1$ | $0.1$ | $9.0 \times 10^{-5}$ |
The rate of the reaction for $[ A ]=0.15 mol dm ^{-3},[ B ]=0.25 mol dm ^{-3}$ and $[ C ]=0.15 mol dm ^{-3}$ is found to be $Y \times 10^{-5} mol dm d ^{-3} s ^{-1}$. The value of $Y$ i. . . . . . .