Bohr's model can explain:

Typical electronic energy gaps in molecules are about $1.0 \ eV$. In terms of temperature,the gap is closest to

$1$ mole of photons, each of frequency $2500 \ s^{-1}$, would have approximately a total energy of:

The dual nature of photons is described by:

In a photoelectric effect experiment, the kinetic energy of an emitted electron is $1.986 \times 10^{-19} \ J$, when a radiation of frequency $1.0 \times 10^{15} \ s^{-1}$ hits the metal. What is the threshold frequency of the metal (in $s^{-1}$)? (Planck's constant $= 6.62 \times 10^{-34} \ J \ s$)

The energy of an electron in an orbit of a hydrogen-like ion with an orbit radius of $52.9 \ pm$ in $J$ is (ground state energy of an electron in a hydrogen atom is $-2.18 \times 10^{-18} \ J$).