Structure of Atom

A bulb is emitted electromagnetic radiation of $660 \mathrm{~nm}$ wavelength. The total energy of radiation is $3 \times 10^{-18} \mathrm{~J}$. The number of emitted photons will be $\left(h=6.6 \times 10^{-34}…

Assertion : The free gaseous $\mathrm{Cr}$ atom has six unpaired electrons. Reason : Half-filled $s$-orbital has greater stability.

Assertion : The chemical properties of different isotopes are same. Reason: Isotopes have same number of neutrons.

If $n=2$ for $\mathrm{He}^{+}$ion then find out the wave length.

Assertion : Fine lines are observed in spectra if an atom is placed in a magnetic field. Reason : Degenerate orbitals split in the presence of magnetic field.

Wavelength of a particular transition for $\mathrm{H}$ atom is $400 \mathrm{~nm}$. What can be the wavelength of $\mathrm{He}^{+}$for the same transition?

In the $\mathrm{P}^{3-}, \mathrm{S}^{2-}$ and $\mathrm{Cl}^{-}$ions, the increasing order of size is

What is the maximum wavelength of line of Balmer series of hydrogen spectrum? $\left(R=1.09 \times 10^7 \mathrm{~m}^{-1}\right)$

The position of both an electron and helium atom is known within $1.0 \mathrm{~nm}$. The momentum of the electron is known within $5.0 \times 10^{-26} \mathrm{~kg} \mathrm{~m} \mathrm{~s}^{-1}$. The minimum uncertainty…

Calculate the velocity of an electron placed in the second orbit of $\mathrm{Li}^{2+}$ ion?

Ionisation potential of hydrogen atom is $13.6 \mathrm{eV}$. Hydrogen atom in ground state is excited by monochromatic light of energy $12.1 \mathrm{eV}$. The spectral lines emitted by hydrogen according to Bohr's…

The $\mathrm{AsF}_5$ molecule is trigonal bipyramidal. The hybrid orbitals used by the As atoms for bonding are