The ionization energy of hydrogen atom (in the ground state) is x kJ. The energy required for an electron to jump from 2nd orbit to the \[{{3}^{rd}}\] orbit will be
Let \[{{v}_{1}}\] be the frequency of the series limit of the Lyman series, \[{{v}_{2}}\] be the frequency of the first line of the Lyman series, and \[{{v}_{3}}\] be the frequency of the series limit of the Balmer series, then
Arrange the following particles in increasing order of values of e/m ratio : electron (e), proton (p), neutron (n) and \[\alpha -\]particle \[(\alpha )\]
Naturally occurring boron consists of two isotopes whose atomic weights are 10.01 and 11.01. The atomic weight of natural boron is 10.81. Calculate the percentage of each isotope in natural boron.
Last line of Lyman series for H-atom has wavelength \[{{\lambda }_{1}}\overset{o}{\mathop{A}}\,,\] \[{{2}^{nd}}\] line of Balmer series has wavelength \[{{\lambda }_{2}}\overset{o}{\mathop{A}}\,\] then
Photon having wavelength 310 nm is used to break the bond of \[{{A}_{2}}\] molecule having bond energy \[288\,kg\,mo{{l}^{-1}}\] then % of energy of photon converted to the K.E. is
\[[hc=12400ev\overset{o}{\mathop{A}}\,,\] \[1ev=96kJ/mol]\]
Table-tennis ball has a mass 10 g and a speed of 90 m/s. If speed can be measured within an accuracy of 4% what will be the uncertainity in speed and position
Photoelectric emission is observed from a surface for frequencies \[{{v}_{1}}\] and \[{{v}_{2}}\] of the incident radiation\[({{v}_{1}}-{{v}_{2}})\]. If the maximum kinetic energies of the photoelectrons in the two cases are in the ratio 1: k then the threshold frequency \[{{v}_{0}}\] is given by
Average atomic mass of magnesium is 24.32 amu. This Mg is composed of 79 mole % of \[^{24}Mg\] and remaining 21 mole % of \[^{25}Mg\] and \[^{26}Mg\]. Calculate the mole % of \[^{25}Mg\]
If in Bohr's model, for unielectronic atom, time period of revolution is represented as \[{{T}_{\,n,Z}}\] where n represents shell no. and Z represents atomic number then the value of \[{{T}_{1,\,2}}:{{T}_{2,\,1}}\] will be:
A hydrogen atom in the ground state is excited by monochromatic radiation of wavelength \[\lambda \overset{o}{\mathop{A}}\,\]. The resulting spectrum consists of maximum 15 different lines. What is the wavelength \[\lambda \]?
From the following list of atoms, choose the no. of pairs of isotopes, isobars and isotones respectively
\[[_{8}^{16}O,_{19}^{39}K,_{19}^{335}U,\] \[_{19}^{40}K,_{7}^{14}N,_{8}^{18}O,\] \[_{6}^{14}C,_{20}^{40}Ca,_{92}^{238}U]\]
For a hypothetical hydrogen like atom, the potential energy of the system is given by \[U(r)=\frac{-k{{e}^{2}}}{{{r}^{4}}}\] where r is the distance between the two particles. If Bohr's model of quantization of angular momentum is applicable, then velocity of particle is given by
The orbital angular momentum for an electron revolving in an orbit is given by \[\sqrt{l(l+1)}\frac{h}{2\pi }\]. This momentum for \[{{d}^{5}},\,{{d}^{6}},\,{{p}^{3}}\] electron will be respectively
An electron, a proton and an alpha particle have kinetic energies of 16E, 4E and E respectively. What is the qualitative order of their de-Broglie wavelengths?
In a sample of H-atom electrons make transition from 5th excited state to ground state, producing all possible types of photons, then number of lines in infrared, region are