Structure of atom practice · Mixed difficulty

An energy of $24.6\,\,eV$ is required to remove one of the electrons from Helium atom. The energy required to remove both electrons from Helium atom is

For a p-electron orbital angular momentum is

Calculate the number of electrons which will together weigh one gram.

The KE of electron in $H{e^ + }$ will be maximum in:

Which of the following configurations is correct for iron ?

When electromagnetic radiation of wavelength $300 \mathrm{~nm}$ falls on the surface of sodium, electrons are emitted with a kinetic energy of $1.68 \times 10^5 \mathrm{~J} \mathrm{~mol}^{-1}$. What is the minimum energy needed to remove an electron from sodium? What is the maximum wavelength that will cause a photoelectron to be emitted?

According to Bohr's atomic theory, which of the following is correct ?

For an atom or ion having single electron, compare the energies of the following orbitals.

$\mathrm{S}_1=$A spherically symmetrical orbital having two spherical nodes.

$\mathrm{S}_2=$ An orbital which is double dumb-bell and has no radial node.

$\mathrm{S}_3=$ An orbital with orbital angular momentum zero and three radial nodes.

$\mathrm{S}_4=$ An orbital having one planar and one radial node.

The orbital angular momentum of an electron in the 3d-orbital is

Given below are two statements:
Statement I Rutherford’s gold foil experiment cannot explain the line spectrum of hydrogen atom.
Statement II Bohr’s model of hydrogen atom contradicts Heisenberg’s uncertainly principle.
In the light of the above statements, choose the most appropriate answer from the options given below:

What is the difference between two species if one has atomic mass $=14$ and atomic number $=7$ whereas the other has atomic mass $=14$ and atomic number $=6$ ?

When electrons are de-exciting to the ground state from $n$th orbit of hydrogen atoms, 15 spectral lines are formed. The shortest wavelength among these will be

Arrange the following type of radiations in increasing order of frequency.

A. Microwaves

B. Amber light from traffic signal

C. Radiation from FM radio

D. Cosmic rays

E. X – rays

Which of the following element will have the same number of electrons in $s$ and as well as $p$-type of orbitals?

The ratio of charge and mass would be greter for

Which of the following set of quantum number is possible?

For which of the following element, all of its existing ion $\mathrm{M}^{{x}+}$ will be diamagnetic?

Bohr’s model can explain

Rutherford's experiment which established the nuclear model of the atom used a beam of

Assertion :- Mass numbers of most of the elements are fractional.

Reason :- Mass numbers are obtained by comparing with the mass number of carbon taken as
12.

The radii of two of the first four Bohr's orbits of the hydrogen atom are in the ratio 1∶4. The energy difference between them may be:

Maximum number of electrons which can be accommodated in a g-subshell is:

$\mathrm{(I)}\,\,\,n = 3,\,\,\,l = 2,\,\,{m_1}\, = - 2$
$\mathrm{(II)}\,\,\,n = 3,\,\,\,l = 1,\,\,\,{m_1} = 0$
$\mathrm{(III)}\,\,\,n = 3,\,\,l = 0,\,\,{m_1} = - 1$
$\mathrm{(IV)}\,\,\,n = 3,\,\,l = 2,\,\,{m_1} = 0$
$\mathrm{(V)}\,\,\,n = 3,\,\,l = 3,\,\,{m_1} = - 2$
Of these question state designation which does not describe an allowed state for an electron in an atom?

Which of the following is not possible for $4 p$ or $3 d$ electrons?

Electron behaves both as a particle and a wave. This was proposed by

The planck’s constant has a unit of :

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

The shape of orbital with $l = 1$ and $m = 0$ is

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: Loss of electron from hydrogen atom results in nucleus of $\sim 1.5 \times 10^{-3} \, \mathrm{pm}$ size.

Reason R: Proton $\left(\mathrm{H}^{+}\right)$always exists in combined form.

In the light of the above statements, choose the most appropriate answer from the options given below:

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.