Question 3 :
Those elements impart colour to the flame on heating in it, the atoms of which require low energy for the ionisation (i.e. absorb energy in the visible region of spectrum). The elements of which of the following groups in Modern periodic table will impart colour to the flame ?
Question 4 :
The energy of hydrogen atom in $n^{th}$ orbits is $E_n$, then the energy in $n^{th}$ orbit of single ionised helium atom will be :
Question 5 :
According to drawback of Rutherford's structure of atom electron should fall in:
Question 6 :
According to the Bhor Theory , which of the following transitions in the hydrogen atom will give rise to the least energetic photon ?
Question 9 :
According to Bohr's theory. energy is..................... when an electron moves from a lower to a higher orbit.
Question 11 :
The sum of the number of neutrons and proton in the isotope of hydrogen is :
Question 12 :
Which of the following electron transition in hydrogen atom will require the energy equivalent to its ionization energy ?
Question 14 :
<div>State True or False.<br/></div>For hydrogen atom, the energies of the sub-shells $4s, 4p, 4d$ and $4f$ are in the order: $4f > 4d > 4p > 4s$.
Question 15 :
The binding energy of $\displaystyle e^{-}$ in the ground state of the hydrogen atom is $13.6\ eV$. The energies required to eject out an electron from three lowest states of H$\displaystyle e^{+}$ atom will be (in eV):
Question 16 :
<p> <font face="Cambria Math, serif">Which is based on nuclear fusion reaction?</font></p>
Question 17 :
The energy difference (in eV) between fourth and second orbits for $H$ atom is :
Question 18 :
The kinetic energy of an electron in the second Bohr orbit of a hydrogen atom is: (${a}_{0}$ is Bohr radius)
Question 19 :
$He^+$ ions are known to have the wavelength difference between first (of the longest wavelength) lines of Balmer and Lyman series equal to $133.7nm$, then calculate the Rydberg constant $R_H$. <br/>
Question 20 :
<p> <font face="Cambria Math, serif">The wave nature of electron was verified by</font></p>