Embibe Experts Solutions for Chapter: Structure of Atom, Exercise 4: Exercise-4

If the value of ${\mathrm{E}}_{\mathrm{n}}=-78.4 \mathrm{k} \mathrm{cal}/\mathrm{mole},$ the order of the orbit in hydrogen atom is:

An electron in an atom jumps in such a way that its kinetic energy changes from $\mathrm{x}$ to $\frac{\mathrm{x}}{4},$ the change in potential energy will be

The ratio of the energy of the electron in ground state of hydroqen to the electron in first excited state of ${\mathrm{Be}}^{3+}$ is

Calculate the energy emitted when electrons of $1.0 \mathrm{g}$ atom of hydrogen undergo transition giving the spectral lines of lowest energy in the visible region of its atomic spectra.${\mathrm{R}}_{\mathrm{H}}=1.1\times {10}^7 {\mathrm{m}}^{-1}, \mathrm{c}=3\times {10}^8 \mathrm{m} {\sec }^{-1}$ and $\mathrm{h}=6.62\times {10}^{-34} \mathrm{J} \sec$

${\mathrm{S}}_1 :$ Bohr model is applicable for ${\mathrm{Be}}^{2+}$ ion.
${\mathrm{S}}_2 :$ Total energy coming out of any light source is an integral multiple of the energy of one photon.
${\mathrm{S}}_3 :$ Number of waves present in the unit length is the wave number.

${\mathrm{S}}_4 : \mathrm{e}/\mathrm{m}$ ratio in cathode ray experiment is independent of the nature of the gas.

The ratio of the slopes of ${\mathrm{K}}_{\max }$ vs $\mathrm{\nu }$ and ${\mathrm{V}}_0$ vs $\mathrm{\nu }$ curves in the photoelectric effects gives

($\mathrm{\nu }=$ frequency, ${\mathrm{K}}_{\max }=$ maximum kinetic energy, ${\mathrm{V}}_0=$ stopping potential)

The ion which has $18$ electrons in the outermost shell is

Boron nitride is isoelectronic with: