The ratio of the wavelengths of the light absorbed by a Hydrogen atom when it undergoes $n=2 \rightarrow n=3$ and $n=4 \rightarrow$ $\mathrm{n}=6$ transitions, respectively, is
If the molar conductivity $\left(\Lambda_{\mathrm{m}}\right)$ of a $0.050 \mathrm{~mol} \mathrm{~L}^{-1}$ solution of a monobasic weak acid is $90 \mathrm{~S} \mathrm{~cm}^2 \mathrm{~mol}^{-1}$, its extent (degree) of dissociation will be
[Assume $\Lambda_{+}^{\circ}=349.6 \mathrm{~S} \mathrm{~cm}^2 \mathrm{~mol}^{-1}$ and $\Lambda_{-}^{\circ}=50.4 \mathrm{~S} \mathrm{~cm}^2 \mathrm{~mol}^{-1}$.]
5 moles of liquid X and 10 moles of liquid Y make a solution having a vapour pressure of 70 torr. The vapour pressures of pure $X$ and $Y$ are 63 torr and 78 torr respectively. Which of the following is true regarding the described solution?
Among the following, choose the ones with equal number of atoms.
A. 212 g of $\mathrm{Na}_2 \mathrm{CO}_3(\mathrm{~s})$ [molar mass $=106 \mathrm{~g}$ ]
B. 248 g of $\mathrm{Na}_2 \mathrm{O}(\mathrm{s})$ [molar mass $=62 \mathrm{~g}$ ]
C. 240 g of $\mathrm{NaOH}(\mathrm{s})$ [molar mass $=40 \mathrm{~g}$ ]
D. 12 g of $\mathrm{H}_2(\mathrm{~g})$ [molar mass $=2 \mathrm{~g}$ ]
E. 220 g of $\mathrm{CO}_2(\mathrm{~g})$ [molar mass $=44 \mathrm{~g}$ ]
Choose the correct answer from the options given below: