Atomic Structure Questions

Of the following sets which one does NOT contain isoelectronic species?

Which of the following statements in relation to the hydrogen atom is correct?

In a multi-electron atom, which of the following orbitals described by the three quantum numbers will have the same energy in the absence of magnetic and electric fields?(a) $n=1,l=0,m=0$ (b) $n=2,l=0,m=0$ (c) $n=2,l=1,m=1$ (d) $n=3,l=2,m=1$ (e) $n=3,l=2,m=0$

Which of the following sets of quantum numbers represents the highest energy of an atom?

Uncertainty in the position of an electron ($\text{mass}=9.1\times 10^{-31}\text{kg}$) moving with a velocity $300\text{m/s}$, accurate up to $0.001\%$, will be ($h=6.63\times 10^{-34}\text{Js}$):

According to Bohr’s theory, the angular momentum of an electron in $5\text{th}$ orbit is:

The wavelength of the radiation emitted, when in a hydrogen atom an electron falls from infinity to stationary state $1$, would be (Rydberg constant $R=1.097\times 10^7{\text{m}}^{-1}$):

Consider the ground state of a $\text{Cr}$ atom ($Z=24$). The number of electrons with azimuthal quantum numbers $l=1$ and $l=2$ are respectively:

Which of the following sets of quantum numbers is correct for an electron in a $4f$ orbital?

Which one of the following constitutes a group of isoelectronic species?

The ionization enthalpy of hydrogen atom is $1.312\times 10^6\text{J/mol}$. The energy required to excite the electron in the atom from $n=1$ to $n=2$ is:

In an atom, an electron is moving with a speed of $600\text{m/s}$ with an accuracy of $0.005\%$. Certainty with which the position of the electron can be located is ($h=6.6\times 10^{-34}{\text{kg m}}^2{\text{s}}^{-1}$, mass of electron $m_e=9.1\times 10^{-31}\text{kg}$):

Calculate the wavelength (in nanometer) associated with a proton moving at $1.0\times 10^3\text{m/s}$. (Mass of proton $=1.67\times 10^{-27}\text{kg}$ and $h=6.63\times 10^{-34}\text{J s}$):

The energy required to break one mole of $\text{Cl}-\text{Cl}$ bonds in ${\text{Cl}}_2$ is $242{\text{kJ mol}}^{-1}$. The longest wavelength of light capable of breaking a single $\text{Cl}-\text{Cl}$ bond is ($c=3\times 10^8{\text{m s}}^{-1}$ and $N_A=6.02\times 10^{23}{\text{mol}}^{-1}$):

Ionisation energy of ${\text{He}}^{+}$ is $19.6\times 10^{-18}{\text{J atom}}^{-1}$. The energy of the first stationary state ($n=1$) of ${\text{Li}}^{2+}$ is:

A gas absorbs a photon of $355\text{nm}$ and emits at two wavelengths. If one of the emissions is at $680\text{nm}$, the other is at:

The electrons identified by quantum numbers $n$ and $l$:(a) $n=4,l=1$ (b) $n=4,l=0$ (c) $n=3,l=2$ (d) $n=3,l=1$ Can be placed in order of increasing energy as: