Structure of atom practice · Mixed difficulty

Cathode-ray tube is used in:

Which of the following ions has electronic configuration $\left[ {\mathrm{Ar}} \right]3{d^6}:$

The minimum energy required to eject an electron from an atom is called :

Wavelength of a photon is $2.0 \times {10^{ - 11}}\mathrm{m},h = 6.6 \times {10^{ - 34}}\;\mathrm{Js}.$. The momentum of photon is:

The nucleus and an atom can be assumed to be spherical. The radius of the nucleus of mass no. A is given by $1.25 \times {10^{ - 13}} \times {A^{1/3}}\mathrm{cm}.$. The atomic radius of atom is 1 Å. If the mass no. is 64, the fraction of the atomic volume that is occupied by nucleus is:

When the frequency of light incident on a metallic plate is doubled, the KE of the emitted photoelectrons will be:

Which of the following energy change is less than third balmer transition in $\mathrm{He}^{+}$ ion:

$\mathrm{M}{\mathrm{g}^{2 + }}$ is isoelectrionic with

The ratio of specific charge of an electron to that of proton is

Which of the following particles moving with same velocity would be associated with smaller de-Broglie wavelength?

According to (n+l) rule after completing 'np' level the electron enters to:

Isoelectronic pair among the following is

The angular momentum of electron of H-atom is proportional to:

Which one of the following has unit positive charge and 1 u mass?

The correct set of four 517 the electron of Rubedium atom (Z=37) is

The energy levels for ${\;_z}{A^{\left( { + z - 1} \right)}}$ can be given by:

Magnetic quantum number for the last electron in sodium is:

Which of the following statement(s) is/are incorrect regarding photoelectric effect?

(i) The number of electrons ejected is proportional to the intensity of light.

(ii) There is some time lag between the striking of light beam on the metal surface and the ejection of electrons.

(iii) The kinetic energy of ejected electrons depends upon the brightness of light.

(iv) The kinetic energy of the ejected electron is proportional to the frequency of the incident radiation.

Wavelengths of different radiations are given below, arrange in increasing order of energies
$\lambda \left( A \right) = 300\,nm,\,\lambda \left( B \right) = 30\mu m,\,\lambda \left( C \right) = 3\,nm,\,\lambda \left( D \right) = 30{A^ \circ }$

Different lines in Lyman series of hydrogen spectrum lie in …. Region

Based on equation $\mathrm{E}=-2.178 \times 10^{-18} \mathrm{~J}\left(\frac{Z^2}{n^2}\right)$, certain conclusions are written. Which of them is not correct ?

When an electron moves from higher orbit to a lower orbit … is produced

The frequency of a green light is $6 \times {10^{14}}\mathrm{Hz}.$ Its wavelength is:

The ratio of ionization energy of H-and $B{e^{ + 3}}$ is

The de-Broglie equation applies

Compared to mass of lightest nucleus the mass of an electron is only:

The quantum levels upto n=3 has:

A single electron species in energy level (orbit number $n$ ) with energy $X$ was provided with excess of energy so that it jumps to higher energy level with energy $Y$. If it can emit radiations of six different wavelengths on de-excitement between these two energy levels, then the correct relation is

What is the ration of mass of an electron to the mass of a proton?

The three quantum numbers  $n,l$ and $m$ are the outcome of: