The number of possible lines of Paschenc series when electron jumps from `7^(th)` excited state to ground state ( in hydrogen like atom ) is `:`

The number of possible line of Paschen series when electron jumps from seventh excited state up to ground state (in hydrogen like atom) is :

As an electron makes a transition from an excited state to the ground state of a hydrogen -like atom / ion

As an electron makes a transition from an excited state to the ground state of hydrogen-like atom // ion:

As an electron makes a transition from an excited state to the ground state of a hydrogen - like atom //ion

As an electron makes a transition from an excited state to the ground state of a hydrogen like atom/ion.

As an electron makes a transition from an excited state to the ground state of a hydrogen - like atom /ion

As an electron makes a transition from an excited state to the ground state of a hydrogen - like atom /ion

The ionisation energy of hydrogen is 13.6 eV . The energy of the photon released when an electron jumps from the first excited state (n=2) to the ground state of hydrogen atom is

The ionisation energy of hydrogen is 13.6 eV . The energy of the photon released when an electron jumps from the first excited state (n=2) to the ground state of hydrogen atom is