Embibe Experts Solutions for Chapter: Structure of Atom, Exercise 3: Exercise-3

The work function $\left({\mathrm{W}}_0\right)$ of some metals is listed below. Count the number of metals which will show photoelectric effect when light of $300 \mathrm{nm}$ wavelength falls on the metal.

The maximum number of electrons that can have principal quantum number, $\mathrm{n}=3$, and spin quantum number, ${\mathrm{m}}_{\mathrm{s}}=-\frac{1}{2}$, is

The kinetic energy of an electron in the second Bohr orbit of a hydrogen atom is : (${\mathrm{a}}_0$ is Bohr radius)

In an atom, the total number of electrons having quantum numbers,$\mathrm{n}=4, \left|{\mathrm{m}}_{\mathrm{l}}\right|=1 \mathrm{and} {\mathrm{m}}_{\mathrm{s}}=- 1/2 \mathrm{is}$

The electrons identified by quantum numbers $\mathrm{n}$ and $\mathrm{l}$:
$$\begin{gathered} \left(\mathrm{a}\right) \mathrm{n} = 4, \mathrm{l} = 1 \\ \left(\mathrm{b}\right) \mathrm{n} = 4, \mathrm{l} = 0 \\ \left(\mathrm{c}\right) \mathrm{n} = 3, \mathrm{l} = 2 \\ \left(\mathrm{d}\right) \mathrm{n} = 3, \mathrm{l} = 1 \end{gathered}$$

Can be placed in order of increasing energy as:

Which of the following is the energy of a possible excited state of hydrogen ?

The radius of the second Bohr orbit for hydrogen atom is (Planck's constant $\left(\mathrm{h}\right)=6.6262\times {10}^{-34} \mathrm{Js};$ mass of electron $=9.1091\times {10}^{-31} \mathrm{kg};$ charge of electron $\left(\mathrm{e}\right)=1.60210\times {10}^{-19}\mathrm{C};$ permitivity of vacuum $\left({\mathrm{ϵ}}_0\right)=8.854185\times {10}^{-12} {\mathrm{kg}}^{-1} {\mathrm{m}}^{-3} {\mathrm{A}}^2$)

The outer electron configuration of  $\mathrm{Gd}$ (Atomic No. : $64$) is :-