Maximum frequency of emission is obtained for the transition:
1. n = 2 to n = 1
2. n = 6 to n = 2
3. n = 1 to n = 2
4. n = 2 to n = 6
The life span of atomic hydrogen is:
1. Fraction of one sec
2. One year
3. One hour
4. One day
1. | the first line of the Lyman series. |
2. | the second line of the Balmer series. |
3. | the first line of the Paschen series. |
4. | the second line of the Paschen series. |
1. | \(4E_n\) | 2. | \(\dfrac{E_n}{4}\) |
3. | \(2E_n\) | 4. | \(\dfrac{E_n}{2}\) |
In which of the following systems will the radius of the first orbit (\(n=1\)) be minimum:
1. doubly ionized lithium
2. singly ionized helium
3. deuterium atom
4. hydrogen atom
Energy \(E\) of a hydrogen atom with principal quantum number \(n\) is given by \(E=-\frac{13.6}{n^{2}}~\text{eV}.\) The energy of a photon ejected when the electron jumps from \(n=3\) state to \(n=2\) state of hydrogen is approximately:
1. \(0.85~\text{eV}\)
2. \(3.4~\text{eV}\)
3. \(1.9~\text{eV}\)
4. \(1.5~\text{eV}\)
1. | uses Einstein's photoelectric equation. |
2. | predicts continuous emission spectra for atoms. |
3. | predicts the same emission spectra for all types of atoms. |
4. | assumes that the angular momentum of electrons is quantized. |
The total energy of an electron in the first excited state of a hydrogen atom is about \(-3.4\) eV.
Its kinetic energy in this state will be:
1. \(-6.8~\text{eV}\)
2. \(3.4~\text{eV}\)
3. \(6.8~\text{eV}\)
4. \(-3.4~\text{eV}\)