Values of work function (W$$_0$$) for a few metals are given below
Metal | Li | Na | K | Mg | Cu | Ag |
---|---|---|---|---|---|---|
W$$_0$$/eV | 2.42 | 2.3 | 2.25 | 3.7 | 4.8 | 4.3 |
The number of metals which will show photoelectric effect when light of wavelength $$400 \mathrm{~nm}$$ falls on it is ___________
Given: $$\mathrm{h}=6.6 \times 10^{-34} \mathrm{~J} \mathrm{~s}$$
$$c=3 \times 10^{8} \mathrm{~ms}^{-1}$$
$$e=1.6 \times 10^{-19} \mathrm{C}$$
At $$600 \mathrm{~K}$$, the root mean square (rms) speed of gas $$\mathrm{X}$$ (molar mass $$=40$$ ) is equal to the most probable speed of gas $$\mathrm{Y}$$ at $$90 \mathrm{~K}$$. The molar mass of the gas $$\mathrm{Y}$$ is ___________ $$\mathrm{g} ~\mathrm{mol}^{-1}$$. (Nearest integer)
Three organic compounds A, B and $$\mathrm{C}$$ were allowed to run in thin layer chromatography using hexane and gave the following result (see figure). The $$\mathrm{R}_{\mathrm{f}}$$ value of the most polar compound is ____________ $$\times 10^{-2}$$
The value of $$x$$ in compound 'D' is _________.