18,19
Q18 a.) Consider a hydrogen atom with its electron in the nth orbital. An electromagnetic radiation of wavelength 90 nm is used to ionize the atom. If the kinetic energy of the ejected electron is 10.4 eV, then find the value of n. ( hc = 1242 eV nm)
b.) Name the spectral line series of hydrogen atom which lies in the (i) visible region (ii) ultraviolet region
Q19 a) If the total number of neutrons and protons in a nuclear reaction is conserved, then how energy is absorbed or released in the reaction?
b.) Two radioactive nuclei X and Y with half-life periods 1 hour and 2 hours respectively, initially contain equal number of atoms. Compare their ratio of disintegration after 8 hours
Dear Student,
18 - Balmer Series lies in the visible region and Lyman series lies in the ultraviolet region.
19 - Here proton number and neutron number are conserved in a nuclear reaction; the total rest mass of neutrons and protons is the same on either side of a reaction. However total binding energy of nuclei on the left side need not be the same as that on the right hand side. The difference in these binding energies appears as energy released or absorbed in a nuclear reaction.
Regards
18 - Balmer Series lies in the visible region and Lyman series lies in the ultraviolet region.
19 - Here proton number and neutron number are conserved in a nuclear reaction; the total rest mass of neutrons and protons is the same on either side of a reaction. However total binding energy of nuclei on the left side need not be the same as that on the right hand side. The difference in these binding energies appears as energy released or absorbed in a nuclear reaction.
Regards