Among $\mathrm{Fe}^{3+}, \mathrm{Pb}^{2+}, \mathrm{Cu}^{2+}$ and $\mathrm{Mn}^{2+}$, identify the one that gets precipitated out while passing $\mathrm{H}_2 \mathrm{~S}$ in presence of $\mathrm{NH}_4 \mathrm{OH}$ as group reagent. The highest possible oxidation state of the corresponding metal is
$$ \text { Match the LIST-I with LIST-II } $$
| List - I | List - II | ||
|---|---|---|---|
| Compound | Test | ||
| A. | ![]() |
I. | Hinsberg's reagent test |
| B. | ![]() |
II. | Phthalein dye test |
| C. | ![]() |
III. | Lucas test |
| D. | ![]() |
IV. | TollenтАЩs test |
$$ \text { Choose the correct answer from the options given below : } $$
If 3.365 g of ethanol $(\mathrm{l})$ is burnt completely in a bomb calorimeter at 298.15 K , the heat produced is 99.472 kJ . The $\left|\Delta \mathrm{H}_{\mathrm{f}}{ }^{\circ}\right|$ of ethanol at 298.15 K is
$\_\_\_\_$ $\times 10^2 \mathrm{~kJ} \mathrm{~mol}^{-1}$. (Nearest integer)
Given: Standard enthalpy for combustion of graphite $=-393.5 \mathrm{~kJ} \mathrm{~mol}^{-1}$
Standard enthalpy of formation of water $(\mathrm{l})=-285.8 \mathrm{~kJ} \mathrm{~mol}^{-1}$
Molar mass in $\mathrm{g} \mathrm{mol}^{-1}$ of $\mathrm{C}, \mathrm{H}, \mathrm{O}$ are 12,1 and 16 respectively
For the following reaction at $50^{\circ} \mathrm{C}$ and at 2 atm pressure,
$$ 2 \mathrm{~N}_2 \mathrm{O}_5(\mathrm{~g}) \rightleftharpoons 2 \mathrm{~N}_2 \mathrm{O}_4(\mathrm{~g})+\mathrm{O}_2(\mathrm{~g}) $$
$\mathrm{N}_2 \mathrm{O}_5$ is $50 \%$ dissociated.
The magnitude of standard free energy change at this temperature is $x$.
$x=$ $\_\_\_\_$ $\mathrm{J} \mathrm{mol}^{-1}$ [Nearest integer].
Given : $\mathrm{R}=8.314 \mathrm{~J} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}, \log 2=0.30, \log 3=0.48, \ln 10=2.303$, ${ }^{\circ} \mathrm{C}+273=\mathrm{K}$
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