Structure of atom practice · Medium

The energy of an electron in first Bohr orbit of H-atom is -13.6 eV. The possible energy value of electron in the excited state of $\mathrm{L}{\mathrm{i}^{2 + }}$ is

Electromagnetic radiations of wavelength 240 $\mathrm{nm}$ are just sufficient to ionize sodium atom. The ionization energy of sodium (in $\mathrm{kJ} / \mathrm{mol}$ ) is

The principal quantum number of H-atom orbital, if the electron energy is -3.4 eV, will be

A typical golf ball weighs $40.0 \mathrm{~g}$. If it is moving with a velocity of $20.0 \mathrm{~ms}^{-1}$, its de-Broglie wavelength is

Bond dissociation on energy of $\mathrm{Br}_2$ is $200 \mathrm{~kJ} / \mathrm{mole}$. The longest wavelength of photon that can break this bond would be $\left(N_{\mathrm{A}} \times h c=0.12 \mathrm{~J}\right)$

According to Heisenberg's uncertainty principle, the product of uncertainties in position and velocities for an electron of mass $9.1 \times 10^{-31} {~kg}$ is

Quantum numbers for some electrons are given below

A : $n=4, I=1\qquad$ B : $n=4, I=0\qquad$ C: $n=3, I=2\qquad$ D: $n=3, I=1$

The correct increasing order of energy of electrons

The radius of an orbit of H – atom is $4.77 \times {10^{ - 10}}m$. Then the angular momentum of an electron in this orbit is

A photon of light of wavelength 6000 Å has energy $E$. What will be the wavelength of photon of a light which has energy of photon $4 E$ ?

ASSERTION (A) : Two electrons in an atom can have the same values of four quantum numbers.

REASON (R) : Two electrons in an atom can be present in the same shell, subshell and orbital and have the same spin.

The principal and azimuthal quantum number of electrons in $4 f$ orbitals are

Based on the equation $\Delta E=-2.0 \times 10^{-18} \mathrm{~J}\left(\frac{1}{n_2^2}-\frac{1}{n_1^2}\right)$
the wavelength of the light that must be absorbed to excite hydrogen electron from level $n=1$ to level $n=2$ will be $\left(h=6.625 \times 10^{-34} \mathrm{~J} \mathrm{~s}, c=3 \times 10^8 \mathrm{~m} \mathrm{~s}^{-1}\right)$

Statement-I: Emitted radiation will be $0.408 \times 10^{-19}$ joule when an electron jump from $n=4$ to $n=2$ in $\mathrm{H}$-atom.

Statement-II: Balmer series radiations belong to IR region for hydrogen atom only.

Determine the wavelength of a photon of electromagnetic radiation having energy $2.99 \times 10^{12} \mathrm{~erg} \mathrm{~mol}^{-1} \left(\mathrm{h}=6.625 \times 10^{-34} \mathrm{~Js}\right)$.

The magnetic quantum number for valency electron of sodium is:

If the magnitude of uncertainties in position $(\Delta {x})$ and momentum $(\Delta {p})$ are equal then which of the following relation is correct?

What is the potential energy of electron in 3
orbit of H-atom ?

Radial nodes present in $3 \mathrm{s}$ and $2 \mathrm{p}$-orbitals are respectively

In H-atom, if ‘x’ is the radius of the first orbit, de-Broglie wavelength of an electron in 3rd orbit is

The energy difference will be minimum for which of the following energy levels of $\mathrm{H}$-atom?

The value of charge on the oil droplets experimentally observed were $- 1.6 \times {10^{ - 19}}$ and $- 4 \times {10^{ - 19}}$ coulomb. The value of the electronic charge, indicated by these results is:

Statement (S): The magnetic moment of $\mathrm{Mg}$-atom is more than $\mathrm{K}$-atom as the former has two electrons in outermost shell.

Explanation (E): The magnetic moment of $\mathrm{N}$-atom is more than magnetic moment of $\mathrm{O}$-atom and former has more number of unpaired electrons.

If the speed of the electron in the first Bohr orbit of hydrogen atom be ' $x$ ' then the speed of electron in the third Bohr orbit is

Which of the following set of quantum numbers is impossible for an electron in an atom?

When atomic orbitals are filled according to the Aufbau principle. The $6 \mathrm{p}$ orbitals are filled immediately after the:

Which of the following electron transition in hydrogen atom will require largest amount of energy?

The representation of the ground state electronic configuration of He by box-diagram as is wrong because it violates