Atoms

Find the ratio of energies of photos product due to transition of an electron of hydrogen atom from its (i) second permitted energy level to the first level. and (ii) the highest permitted energy level to the first permitted level.

Given below are two statements:

Statement I : In hydrogen atom, the frequency of radiation emitted when an electron jumps from lower energy orbit (E₁) to higher energy orbit (E₂), is given as hf = E₁ = E₂

Statement II : The jumping of electron from higher energy orbit (E₂) to lower energy orbit (E₁) is associated with frequency of radiation given as f = (E₂ – E₁) / h

This condition is Bohr's frequency condition.

In the light of the above statements, choose the correct answer from the options given below:

In photoelectric effect experiment, the graph of stopping potential $\vee$ versus reciprocal of wavelength obtained is shown in the figure. As the intensity of incident radiation is increased:

The simple Bohr model is not applicable to He⁴atom because
(a) He⁴ is an inert gas 
(b) He⁴ has neutrons in the nucleus
(c) He⁴ has one more electron
(d) Electrons are not subject to central forces

Let E_n= $\frac{-1\mathit{m}{\mathit{e}}^4}{8{\mathit{\epsilon }}_0^2{\mathit{n}}^2{\mathit{h}}^2}$ be the energy of the nth level of H atom. If all the H-atoms are in the ground state and radiation of frequency $\frac{{\mathit{E}}_2-{\mathit{E}}_1}{\mathit{h}}$  falls on it

(a) It will not be absorbed at all

(b) Some of atoms will move to first excited state

(c) All atoms will be excited to the n= 2 state

(d) No atoms will make a transition to then n=3 state

The Balmer series for the H-atom can be observed

(a) If we measure the frequencies of light emitted when an excited atom falls to the ground state

(b) If we measure the frequencies of light emitted due to transitions between excited states and the first excited state

(c) In any transition in a H-atom .

(d) As a sequence of frequencies with the higher frequencies getting closely

The Bohr model for the spectra of a H-atom
(a) Will not be applicable to hydrogen in the molecular form
(b) Will not be applicable as it is for a He-atom
(c) Is valid only at room temperature
(d) Predicts continuous as well as discrete spectral lines

Consider aiming a beam of free electrons towards free protons. When-they scatter, an electron and a proton cannot combine to produce a H-atom.
(a) Because of energy conservation
(b) Without simultaneously releasing energy in the form of radiation
(c) Because of momentum conservation
(d) Because of angular momentum conservation

An ionised H-molecule consists of an electron and two protons. The protons are separated by a small distance of the order of angstrom. In the ground state,
(a) The electron would not move in circular orbits
(b) The energy would be (2)⁴times that of a H-atom
(c) The electrons, orbit would go around the protons
(d) The molecule will soon decay in a proton and a H-atom

A set of atoms in an excited state decays
(a) In general to any of the states with lower energy
(b) Into a lower state only when excited by an external electric field
(c) All together simultaneously into a lower state
(d) To emit photons only when they collide.