Question 1 :
The total energy of the electron revolving around the nucleus is:
Question 2 :
Energy of the electron in hydrogen in its first orbit is:
Question 3 :
If r is radius of first orbit, the radius of nth orbit of the H atom will be :
Question 4 :
<div>State True or False.<br/></div>The velocity of the electron is maximum in the Bohr's last orbit.
Question 6 :
Out of given atoms which atoms has highest energy of 2s-subshell ?
Question 8 :
The ionisation energy for the H atom is 13.6 eV then the requried energy in eV to excite it from the ground state to next higher state will be (in eV) :
Question 11 :
$E_n = - \dfrac{313.6}{n^2}$, if the value of $E_n = - 34.84$ to which value 'n' corresponds:
Question 12 :
A hydrogen atom in the ground state is excited by monochromatic radiation of wavelength $\lambda\ A$ The resulting spectrum consists of maximum $15$ different lines. What is the wavelength$\left( \lambda \right)$ of radiation?$ \left( Given:{ R }_{ H }=109737{ cm }^{ -1 } \right)$
Question 13 :
Which of the following parameters are same for all hydrogen like atoms and ions in their ground state?
Question 14 :
The energy of the electron in the second and third Bohr orbits of the hydrogen atom is -5.42 $\times$ 10$^{-12}$ erg and -2.41 $\times$ 10$^{-12}$ erg, respectively. The wave length of the emitted radiation when the electron drops from third to second orbit will be :
Question 15 :
<p>The maximum wavelength of light that can excite an electron from first to the third orbit of a hydrogen atom is : </p>
Question 18 :
The energy of the second Bohr orbit in the hydrogen atom is $-3.41\ eV$. The energy of the second Bohr orbits of $He^+$ ion would be:
Question 19 :
If first ionisation energy of hydrogen is $E$, then the ionisation energy of ${ He }^{ + }$ would be:
Question 20 :
If the radius of second stationary orbit (in Bohr's atom) is R. Then, the radius of third orbit will be:
Question 21 :
The ratio of $\left({E}_{2}-{E}_{1}\right)$ to $\left({E}_{4}-{E}_{3}\right)$ for the hydrogen atom is approximately equal to:
Question 22 :
Which of the following electron transition in hydrogen atom will require the largest amount of energy?
Question 23 :
<div>A formula analogous to the Rydberg formula applies to the series of spectral lines which arise from transitions from higher energy level to the lower energy level of hydrogen atom.<br/>A muonic hydrogen atom is like a hydrogen atom in which the electron is replaced by a heavier particle, the 'muon'. The mass of the muon is about $207$ times the mass of an electron, while the charge remains same as that of the electron. Rydberg formula for hydrogen atom is:<br/>$\dfrac { 1 }{ \lambda  } ={ R }_{ H }\left[ \dfrac { 1 }{ { n }_{ 1 }^{ 2 } } -\dfrac { 1 }{ { n }_{ 2 }^{ 2 } }  \right] \left( { R }_{ H }=109678{ cm }^{ -1 } \right) $<br/></div>Radius of first Bohr orbit of muonic hydrogen atom is
Question 24 :
In one revolution round the hydrogen nucleus, an electron makes five crests .The electron belongs to<br>
Question 25 :
<div>State whether the given statement is true or false:</div><br/>With the increase in distance from the nucleus, energy of electron increases and the velocity of electron decreases.<br/>
Question 26 :
According to the Bohr model of the atom, which electron transition will emit the lowest energy photon?
Question 27 :
The ionisation energy for excited hydrogen atom in eV will be :
Question 28 :
As an electron is brought from an infinite distance close of nucleus of the atom, the energy of electron:
Question 29 :
The maximum possible values of magnetic orbital quantum number ($m_{l})$ are
Question 30 :
The Bohr orbit radius for the hydrogen atom $(n = 1)$ is approximately $0.530 \mathring{A}$ The radius for the first excited state $(n = 2)$ will be:
Question 31 :
The velocity of electron in third excited state of $\displaystyle Be^{3+}$ will be:
Question 32 :
The approximate value of quantum number $'n\ '$ for the circular orbit of hydrogen of $0.0001\space mm$ in diameter is
Question 33 :
For the energy levels in an atom which one of the following statements is(are) correct?
Question 34 :
What is the maximum number of electrons present in the main energy level in which the 'g' subshell appears for the first time?
Question 35 :
For any H like system, the ratio of velocities of orbit I, II & III  i.e. $\displaystyle V_{1}: V_{2}: V_{3}$ will be :
Question 36 :
The ratio of the difference in energy between the first and second Bohr orbits to between the second and third Bohr orbit is:
Question 37 :
Consider a hypothetical hydrogen like atom. The wavelength in $A^o$ for the spectral lines for transition from $n=p$ to $n=1$ are given by:<br/>$\lambda =\displaystyle\frac{1500p^2}{p^2-1},$ where $p > 1$<br/>Find the ionization potential of this element?<br/>
Question 38 :
The possible subshells in $n = 3$ energy shell are :
Question 39 :
Among 4p, 4s, and 3d orbitals, 3d orbital has the least energy.
Question 40 :
The first ionization energy of $N$ & $O$ are __________ respectively .
Question 41 :
There are seven orbitals in a subshell then the value of $l$ for it will be
Question 42 :
The radius of hydrogen atom in the ground state is $5.3\times10^{-11} m$. When struck by an electron, its radius is found to be $21.2\times10^{-11}m$. The principal quantum number of the final state will be
Question 45 :
The energy of the second Bohr orbit of the hydrogen atom is $-3.41\ eV$. The energy of the third Bohr orbit of the $He^+$ ion will be
Question 46 :
A small particle of mass $m$ moves in such a way that $P.E=-\displaystyle \frac{1}{2}mkr^{2}$, where $k$ is a constant and $r$ is the distance of the particle from origin. Assuming Bohr's model of quantization of angular momentum and circular orbit, $r$ is directly proportional to:
Question 47 :
The two electrons have the following sets of quantum numbers.<br/>X: 3, 2, -2, +1/2<br/>Y: 3, 0, 0, + 1/2<br/>What is true of the following?
Question 48 :
 Bohr's radius for the fifth orbit of the hydrogen atom in $A^0$ is :
Question 49 :
The energy of second orbit of hydrogen is equal to the energy of:
Question 50 :
The radius of the second Bohr orbit for hydrogen atom is:<div><br/>[Given: Planck's const. $h = 6.6262\times 10^{-34}Js$; mass of electron $= 9.1091\times 10^{-31}kg$; charge of electron, $e=1.60210\times 10^{-19}C$; permittivity of vacuum, $\varepsilon _0=8.854185\times 10^{-12}kg^{-1}m^{-3}A^2$]<br/></div>
Question 51 :
In a hydrogen atom, an electron jumps from the third orbit to the first orbit. Find out the frequency of the spectral line. $\left( { R }_{ H }=1.09678\times { 10 }^{ 7 }{ m }^{ -1 } \right) $.
Question 52 :
Not considering the electron spin, the degeneracy of second excited state is 9, while the generality of the first excited state of $H$ atom is: 
Question 53 :
The ionization energy of hydrogen atom is $13.6eV.$ The energy required to excite the electron in a hydrogen atom from the ground state to the first excited state is:<br>
Question 54 :
According to de-Broglie wavelength for electron in an orbit of hydrogen atom is $10^{-9}\ m$. The principle quantum number for this electron is
Question 55 :
What is likely to be principal quantum number for a circular orbit of diameter 20 nm of the hydrogen atom, if we assume Bohr orbit be the same as that represented by the principal quantum number?
Question 56 :
A particle of mass $m$ moves around in a circular orbit in a centro symmetric potential field u(r)$=\dfrac{kr^{2}}{2}$. Using Bohr’s quantization rule, the permissible energy levels are <br/>
Question 57 :
The total energy of a hydrogen atom in its ground state is $-13.6\ eV$. If the potential energy in the first excited state is taken as zero then the total energy in the ground state will be:
Question 58 :
A hydrogen-like atom (atomic number $Z$) is in a higher excited state of the quantum number $n$. This excited atom can make a transition to the first excited state by successfully emitted to photons of energies $10.20eV$ and $17.00eV$ respectively.<div>       Alternatively, the atom from the same excited state can make a transition to the second excites state by the successively emitting two photons of energy $4.25ev$ and $5.95ev$ respectively. Determine the values of $n$ and $Z$ (ionization energy of hydrogen atom $=13.6eV$).<br/></div>
Question 59 :
Consider a hydrogen like atom whose energy in $\displaystyle { n }^{ th }$ excited state is given by $\displaystyle { E }_{ n }=-\frac { 13.6 }{ { n }^{ 2 } } { Z }^{ 2 }$. When this excited atom makes a transition from an excited state to ground state. The most energetic photons have energy $\displaystyle { E }_{ max }=52.224eV$ and the least energetic photons have energy $\displaystyle { E }_{ min }=1.224eV$. Find the atomic number of atom.<br/>
Question 60 :
The ratio of ground state energy of $Li^{2+}, He^+$ and H is :
Question 61 :
The energy of the second Bohr orbit in the hydrogen atom is $-3.41 \,eV.$ The energy of the second Bohr orbit of $He^{+}$ ion would be:
Question 62 :
What is the energy required to move the electron from the ground state of H atom to the first excited state? Given that the ground state energy of H atom is 13.6 eV and that the energy E$_n$ of an electron in n$^{th}$ orbital of an atom or ion of atomic number Z is, given by the equation $E_n =(13.6Z^2/n^2)$
Question 63 :
The wavelength($\lambda_n$) of the pion orbiting in nth stationary state is given by
Question 64 :
The energy difference (in eV) between fourth and second orbits for $H$ atom is :
Question 65 :
Number of waves made by the pion when orbiting in third excitation state are
Question 67 :
The quantum number n of the state finally populated in $He^{+}$ ions is <br/>
Question 68 :
<div>For $H$-like atoms :</div><div>      </div><div>            $\displaystyle E_n=-\frac{Z^2Rh}{n^2};u_n=\frac{u_1Z}{n}$ and $r_n=\frac{r_1\times n^2}{Z};$ where $Rh$ is Rydberg.<br/></div><br/>What is the potential energy of electron in $2^{nd}$ orbit of $H$-atom?<br/>
Question 69 :
Calculate the ratio of energies of $2^{nd}$ orbits of hydrogen, $He^+, Li^{+2}$.<br/>
Question 71 :
Assertion: 3s, 3p and 3d subshells of hydrogen have the same energy. <br/>Reason: Energy of subshells in the hydrogen atom, depends on the principal quantum number (n) and azimuthal quantum number (l). <br/>
Question 72 :
The longest wave length radiation emitted in the emission spectrum when the pion de-excites from n = 3 to ground state lies in which of the following region?
Question 73 :
The number of revolutions of an electron in the second Bohr orbit in one second is:<br>
Question 74 :
Consider the hydrogen atom to be a proton embedded in a cavity of radius $a_0$ (Bohr's radius), whose charge is neutralized by the addition of an electron to the cavity in vacuum, infinitely slowly. Then the wavelength of the electron when it is at a distance of $a_0$ from the proton will be <br/>
Question 75 :
Electrons accelerated by potential V are diffracted from a crystal. If $\mathrm{d}= 1\mathrm{A}$ and $\mathrm{i}=30^{0},\ \mathrm{V}$ should be about: <div>[$\mathrm{h}=6.6\times 10^{-34}$ Js, $\mathrm{m}_{\mathrm{e}}=9.1\times 10^{-31}$ kg, $\mathrm{e}=1.6\times 10^{-19}\mathrm{C}$]<br/></div>
Question 76 :
If the wavelength of the photon emitted from an electron jump n $=$ 4 to n $=$ 2 in a H-like species is 1216 $\overset{o}{A}$, then the species is :
Question 77 :
If the PE of a Bohr's hydrogen atom in the ground state is zero, then its total energy in the first excited state will be :
Question 78 :
Check the correctness of the following statements about the Bohr Model of hydrogen atom:<br>$(i)$ The acceleration of the electron in $n=2$ orbit is more than that in $n=1$ orbit.<br>$(ii)$ The angular momentum of the electron in $n=2$ orbit is more than that in $n=1$ orbit.<br>$(iii)$ The KE of the electron in $n=2$ orbit is less than that in $n=1$ orbit
Question 79 :
If elements of quantum number greater than $'n'$ were not allowed, the number of possible elements in nature would have been
Question 80 :
The only electron in the hydrogen atom resides under ordinary conditions on the first orbit. When energy is supplied, the electron moves to higher energy orbit depending on the amount of energy absorbed. When this electron returns to any of the lower orbits, it emits energy. Lyman series is formed when the electron returns the lowest orbit while Balmer series is formed when the electron returns to the second orbit. Similarly, Paschen, Brackett, and Pfind series are formed when electron returns to the third, fourth, and fifth from higher orbits, respectively.<br/>Maximum number of lines produced when an electron jumps from  nth level to ground level is equal to $\displaystyle\frac{n(n - 1)}{2}$. <br/><i></i>If the electron comes back from the energy level having energy E$_2$ to the energy level having energy E$_1$, then difference may be expressed in terms of energy of photon as<br/>E$_2$ - E$_1$ = $\Delta$E, $\lambda$ = hc/$\Delta$E<br/>Since h and c are constant, $\Delta$E corresponds to definite energy, thus, each transition from one energy level to another will produce a light of definite wavelength. This is actually observed as a line in the spectrum of hydrogen atom.<br/>Wave number of line is given by the formula<br/>v = $RZ^2\left( \displaystyle\frac{1}{n_1^2} - \frac{1}{n_2^2}\right)$<br/>where R is a Rydberg constant.The wave number of electromagnetic radiation emitted during the transition of electron in between the two levels of Li$^{2+}$ ion whose principal quantum numbers sum is 4 and difference is 2 is :
Question 81 :
The ionization energy of hydrogen atom is $13.6$ eV. The longest wavelength of hydrogen spectrum in the ultraviolet region is expected to be:
Question 82 :
The ratio of speed of electron in $I$ orbit of $H$-atom to $IV$ orbit of $He^+$ ion is :<br/>