Ozone is formed by the reaction
$$ \mathrm{O}_{2(g)}+\mathrm{O}_{(g)} \rightarrow \mathrm{O}_{3(g)}, \Delta \mathrm{H}=-107.2 \mathrm{~kJ} . $$
Given $\mathrm{O}=0$ bond energy is $498.0 \mathrm{~kJ} \mathrm{~mol}^{-1}$, the average bond energy of ozone is:
$302.6 \mathrm{~kJ} \mathrm{~mol}^{-1}$
$520.6 \mathrm{~kJ} \mathrm{~mol}^{-1}$
$120.5 \mathrm{~kJ} \mathrm{~mol}^{-1}$
$201.8 \mathrm{~kJ} \mathrm{~mol}^{-1}$
The number of structural isomers possible for a compound with molecular formula $\mathrm{C}_3 \mathrm{H}_9 \mathrm{~N}$ is:
3
4
2
5
$$ \text { Match the mixtures listed in Column I with the correct method used for their separation. } $$
| $$ \text { Column I } $$ |
$$ \text { Column I } $$ |
||
|---|---|---|---|
| A | Glycerol from spent Lye | P | Steam distillation |
| B | Mixture of Benzoic acid and Naphthalene dissolved in organic solvent | Q | Distillation |
| C | Aniline & Chloroform | R | Distillation under reduced pressure |
| D | 2- Nitrophenol & 4- Nitrophenol | S | Differential extraction using $\mathrm{NaHCO}_3$ |
$$ A-Q \quad B-R \quad C-S \quad D-P $$
$$ A-Q \quad B-R \quad C-S \quad D-P $$
$$ A-R \quad B-S \quad C-Q \quad D-P $$
$$ A-R \quad B-P \quad C-S \quad D-Q $$
An aqueous solution of an unknown solute " $X$ " is prepared by adding 4.0 g of it into 2.0 moles of water. What is the mass percent of " $X$ " in the aqueous solution?
20
40
15
10
COMEDK Papers
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