The frequency of photon which is emitted during a transition of electron of $\mathrm{He}^{+}$ion from fifth energy level to third energy level will be:
$1.34 \times 10^{-14} \mathrm{~s}^{-1}$
$9.39 \times 10^{14} \mathrm{~s}^{-1}$
$2.34 \times 10^{14} \mathrm{~s}^{-1}$
$8.29 \times 10^{-14} \mathrm{~s}^{-1}$
$$ \text { Match the reactions in List I with the final products formed as given in List II. } $$
| $$ \text { List I } $$ |
$$ \text { List II } $$ |
||
|---|---|---|---|
| W | $$ \mathrm{C}_6 \mathrm{H}_5 \mathrm{CH}_3 \frac{(\text { i }) \mathrm{CrO}_3+\left(\mathrm{CH}_3 \mathrm{CO}\right)_2 \mathrm{O}}{(\text { ii }) \mathrm{H}_3 \mathrm{O}+\text { heat }} \rightarrow $$ |
P | $$ \mathrm{R}_2 \mathrm{CO} $$ |
| X | $$ \mathrm{RCOOC}_2 \mathrm{H}_5 \frac{(\text { i) } D I B A L-H}{(\text { ii }) \mathrm{H}_2 \mathrm{O}} \rightarrow $$ |
Q | $$ \mathrm{C}_6 \mathrm{H}_5 \mathrm{COCH}_3 $$ |
| Y | $$ R C N \frac{(i) R-\mathrm{Mg}-\mathrm{X} / \text { dry ether }}{(i i) \mathrm{H}_3 \mathrm{O}^{+}} \rightarrow $$ |
R | $$ \mathrm{C}_6 \mathrm{H}_5 \mathrm{CHO} $$ |
| Z | $$ \mathrm{C}_6 \mathrm{H}_5 \mathrm{COCl}+\left(\mathrm{CH}_3\right)_2 \mathrm{Cd} \text { in dry ether → } $$ |
S | $$ \mathrm{RCHO} $$ |
$$ W-Q \quad X-P \quad Y-S \quad Z-R $$
$$ W-R \quad X-P \quad Y-Q \quad Z-S $$
$$ W-R \quad X-S \quad Y-P \quad Z-Q $$
$$ W-S \quad X-R \quad Y-Q \quad Z-P $$
$$ \text { The product formed in the following reaction is: } $$





How many molecules of $\mathrm{CO}_2(\mathrm{~g})$ are obtained on reaction of 24 grams of methane with 4 moles of oxygen?
$3.011 \times 10^{23}$
$12.044 \times 10^{23}$
$6.022 \times 10^{23}$
$9.033 \times 10^{23}$
COMEDK Papers
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