Atomic Structure · Chemistry · COMEDK
MCQ (Single Correct Answer)
The frequency of photon which is emitted during a transition of electron of $\mathrm{He}^{+}$ion from fifth energy level to third energy level will be:
Which of the following statement is correct?
In the photoelectric emission, the energy of the emitted electron is:
The Bohr orbit of the hydrogen atom ( $n=1$ ) is $0.530 \mathop {\rm{A}}\limits^{\rm{o}} $. The radius of the first excited state orbit in $\mathop {\rm{A}}\limits^{\rm{o}} $ is:
What is the wave number (Units $$\mathrm{cm}^{-1}$$) of the longest wave length transition in the Balmer series of Hydrogen spectrum? $$Z=1 \text { for } H$$
The correct sequence of filling of electrons in $$n=6$$ is:
The ratio of the first three radii of Bohr's atom is:
A statement of Assertion followed by a statement of Reason is given. Choose the correct answer out of the following options.
Assertion : Energy of $$2 \mathrm{~s}$$ orbital of Hydrogen is less than the energy of the $$2 \mathrm{~s}$$ orbital of Lithium.
Reason : Energies of orbitals in the same subshell decrease with increase in atomic number.
Given below are 4 subatomic particles travelling with the same velocity "v". Which of them will have the shortest wavelength?
$$[A]=\text { Proton }[B]=\text { Neutron. }[C]=\text { Alpha particle. }[D]=\text { Electron. }$$
The mass number of an element $$\mathrm{X}$$ is 175 with 104 neutrons in its nucleus. Into which one of the following orbitals will the last electron enter?
Bohr's radius of 2 nd orbit of $$\mathrm{Be}^{3+}$$ is equal to that of
The ion that is isoelectronic with $$\mathrm{CO}$$ is
A proton having mass equal to $$1.66 \times 10^{-27} \mathrm{~kg}$$ is accelerated to one tenth of the velocity of light. If its velocity can be measured to an accuracy of $$\pm 2 \%$$, what would be the uncertainty in its position?
The energy of an electron in the ground state of Hydrogen atom is $$-2.18 \times 10^{-18} \mathrm{~J}$$. What would be the energy associated with the second excited state of $$\mathrm{Li}$$ ?
Minimum number of nodes are present in
$$\mathrm{O^{2-},F^-,Mg^{2+},Al^{3+},O_2,F_2}$$. How many of the species given above isoelectronic?
The spectrum of He$$^+$$ is similar to
The Paschen series of hydrogen spectrum lies in which region?
The total number of nodes are given by
Which of the following series of transitions in the spectrum of hydrogen atom fall in visible region?
The Lyman series of hydrogen spectrum lies in which region
A body of mass 10 mg is moving with a velocity of 100 ms$$^{-1}$$. The wavelength of de-Broglie wave associated with it would be
($$h=6.63\times10^{-34}$$ Js)
Mg$$^{2+}$$ is isoelectronic with