Taking the Bohr radius as a₀ = 53pm, the radius of Li⁺⁺ ion its ground state, on the basis of Boh''s model, will be about

O₂ molecule consists of two oxygen atoms.In the molecule, nuclear force between the nuclei of the two atoms

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,

Write an expression for Bohr's radius in hydrogen atom.

Name the spectral series of hydrogen atom, which is in infrared region.

Does the ratio of neutrons and protons in the nucleus increase, decreases or remain the same after the emission of \(\alpha\) – particles?

A radio isotope of silver has a half life of 20 minutes. What fraction of the original mass would remain after one hour?

Can a single nucleus emit \(\alpha\) – particle, \(\beta\) – particle and a γ – rays together?

What is the impact parameter for scattering of \(\alpha \)- particle by \(180°\)?

The electron, in a hydrogen atom, is in its second excited state. Calculated the wavelength of the lines in the Lyman series, that can be emitted through the permissible transitions of this electron. (Given the value of Rydberg constant, R = 1.1 x 10⁷ m^-1)

Write nuclear equations for
a) The \(\alpha\)-decay of ²²⁶Ra₈₈
b) The \(\beta\)^- -decay of ³²P₁₅
c) The \(\beta\)⁺ decay of ³²P₁₅

A neutron is absorbed by a ⁶Li3 nucleus with the subsequent emission of an alpha particle.
i) Write the corresponding nuclear reactions.
ii) Calculate the energy released in MeV, in this reaction.
Given mass ⁶Li3 = 6.0151264; mass (neutron) = 1.00966544
Mass (alpha particle) = 4.00260444 and mass(triton) = 3.01000004

'The half life \(_{ 6 }^{ 14 }{ C }\) is 5700 years.' What does it mean ?
Two radioactive nuclei X and Y initially contain an equal number of atoms. Their half life is 1 hour and 2 hours respectively. Calculate the ratio of their rates of disintegration after two hours.

The gravitational attraction between electron and proton in a hydrogen atom is weaker than the Coulomb attraction by a factor of about 10^-40. An alternative way of looking at this fact is to estimate the radius of the first Bohr orbit of hydrogen atom if the electron and proton were bound by gravitational attraction. You will find the answer interesting.

An \(\alpha \)- particle of K.E.\({ 10 }^{ -12 }\)J exhibits backscattering from a gold nucleus Z = 79. What can be the maximum possible radius of the gold nucleus?

Calculate shortest wavelength of Balmer series. Given \(R=1.097\times { 10 }^{ 7 }{ m }^{ -1 }\).

A radioactive material is reduced to of\(\frac { 1 }{ 16 } \) its original amount in 4 days. How much material should one begin with so that of \(4\times { 10 }^{ -3 }kg\) the material is left after 6 days?

Nuclear fission is the phenomenon of splitting of a heavy nucleus into two or more lighter nuclei. Nuclear fussion is the phenomenon of fusing two or more lighter nuclei to form a single heavy nucleus. In both these processes, a certain mass \(\left( \Delta m \right) \) disappears, which appears in the form of nuclear energy, \(E=\left( \Delta m \right) { c }^{ 2 }.\) The release of energy is so sudden that it cannot be controlled. This causes havoc. Nuclear fission is the basis of an atom bomb and nuclear fusion is the basis of a nydrogen bomb. A powerful device, called Nuclear Reactor has been developed, where in nuclear energy produced is utilised for constructive purposes.
Read the above passage and answer the following questions:
(i) How much energy is released in the fission of one nucleus of \({ U }^{ 235 }\) and in how much time?
(ii) Give an estimate of devastation potential of an atomic explosion.
(iii) Should we ban nuclear research in this field? Give your views briefly.