Structure of atom practice · Hard

Determine the number of revolutions made by electron in one second in the $2^{\text {nd }}$ Bohr orbit of hydrogen atom. (Take $r_0=0.53 \times 10^{-10} \mathrm{~m}$ )

Statement-1 : Nuclide ${ }^{30} {Al}_{13}$ is less stable than ${ }^{40} {Ca}_{20}$

Statement-2 : Nuclide having odd number of protons and neutrons are generally unstable.

The total spin resulting from a ${d^7}$ configuration is:

Photons having energy equivalent to binding energy of $4^{\text {th }}$ state of $\mathrm{He}^{+}$ion is used on the metal surface of work function $1.4 \mathrm{eV}$. If electrons are further accelerated through
the potential difference of $4 \mathrm{~V}$ then the minimum value of de-Broglie wavelength associated with the electron is

What is the mass of a photon of sodium light with a wavelength of 5890 ${A^0}?(h = 6.63\mathrm{ \times }{10^{ - 27}}erg - s)$

Bohr’s radius of 2nd orbit of $\mathrm{B}{\mathrm{e}^{3 + }}$ is equal to that of

The mass defect of the nuclear reaction: ${ }_5 {B}^8 \rightarrow{ }_4 {Be}^8+{e}^{+}$is

$\mathrm{Be}^{3+}$ and a proton are accelerated by the same potential, their de-Broglie wavelengths have the ratio (assume mass of proton = mass of neutron) :

Calculate the wavelength of light required to break the bond between two chlorine atoms in a chlorine molecule. The $\mathrm{Cl}-\mathrm{Cl}$ bond energy is $243 \mathrm{KJ} / \mathrm{mol} .\left(h=6.6 \times 10^{-34} \mathrm{Js}\right)$

The ionisation enthalpy of hydrogen atom is $1.312 \times {10^6}\mathrm{Jmo}{\mathrm{l}^{ - 1}}$. The energy required to excite the electron in the atom from ${n_1} = 1\;\mathrm{to }\;{n_2} = 2$ is

Oxygen consists of ${\mathrm{O}^{16}},{\mathrm{O}^{17}}\mathrm{\;and\;}{\mathrm{O}^{18}}$ isotopes and carbon consists of isotopes of ${\mathrm{C}^{12}}$ and ${\mathrm{C}^{13}}$. Total number of $C{O_2}$ molecules possible are:

A single electron species in energy level (orbit number $n$ ) with energy $X$ was provided with excess of energy so that it jumps to higher energy level with energy $Y$. If it can emit radiations of six different wavelengths on de-excitement between these two energy levels, then the correct relation is

The ratio of the difference in energy between the first and the second Bohr orbit to that between the second and the third Bohr orbit is

$\mathrm{O}_2$ undergoes photochemical dissociation into one normal oxygen atom and one oxygen atom, 1.2 $\mathrm{eV}$ more energetic than normal. The dissociation of $\mathrm{O}_2$ into two normal atoms of oxygen requires $482.5 \mathrm{~kJ} / \mathrm{mol}$. The maximum wavelength effective for photochemical dissociation of $\mathrm{O}_2$ is $(1 \mathrm{eV}=$ $96.5 \mathrm{~kJ} / \mathrm{mol}$ )

Binding energy of hydrogen atom is 13.6 eV. The binding energy of a singly ionised helium atom is:

Which of the following energy change is less than third balmer transition in $\mathrm{He}^{+}$ ion:

Calculate the velocity of an electron having wavelength of 0.15 nm Mass of an electron is $9.109 \times {10^{ - 28}}g$. $\left( {h = 6.626 \times {{10}^{ - 27}}\,erg - s} \right)$

Energy for $7.25 \times 10^{15}$ photons of $5.37 \times 10^{14} \mathrm{~s}^{-1}$ frequency in Einstein unit is

Given that in the H-atom the transition energy for $n = 1\,to\,n = 2$, 10.2eV, the energy for the same transition in $\mathrm{B}{\mathrm{e}^{3 + }}$ is:

What is the de Broglie wavelength? Assume that one mole of protons has a mass equal to $1 \mathrm{~g}?$ $(h=6.626 \times$ $10^{-27} \text{erg s})$

Energy required to stop the ejection of electrons from ${Cu}$ plate is $0.24\, \mathrm{eV}$. If radiation of $\lambda=253.7 \mathrm{~nm}$ strikes the plate, the work function is

Photons having energy equivalent to binding energy of $4^{\text {th }}$ state of $\mathrm{He}^{+}$ion is used on the metal surface of work function $1.4 \mathrm{eV}$. If electrons are further accelerated through
the potential difference of $4 \mathrm{~V}$ then the minimum value of de-Broglie wavelength associated with the electron is