Hydrogen like atoms (atomic number `= Z`) in a sample are in excited state with principal quantum number n. The emission spectrum of the sample has `15` different lines. The second most energetic photon emitted by the sample has energy of `27.2 eV`. Find Z.
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A photon of energy `12.09 eV` is completely absorbed by a hydrogen atom initially in the ground state. The quantum number of excited state is
Correct Answer - C Energy difference in hydrogen atom `= 13.6 - (13.6)/(n^(2)) = 12.09 rArr n^(2) ~~ 9 rArr n = 3`
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When a hydrogen atom is excited from ground state to first excited state then
Correct Answer - D In ground state , kinetic energy `= 13.6 eV`, Potential energy `= -27.2 eV` In first excited state, kinetic energy `= 3.4 eV`, Potential energy `= -...
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An electron in hydrogen atom first jumps from second excited state to first excited state and then from first excited state to ground state. Let the r
Correct Answer - B `E_(1) = (hc)/(lambda) [(1)/(n_(1)^(2)) - (1)/(n_(2)^(2))]` For second excited state to first excited state `E_(1) = (hc)/(lambda) [1/4 - 1/9] rArr (hc)/(lambda) ((5)/(36))` For first excited state...
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If the binding energy of `2^(nd)` excited state of a hydrogen like sample os `24 eV` approximately, then the ionisation energy of the sample is approx
Correct Answer - D `(13.6(Z)^(2))/((3)^(2))=24` I.E. `=13.6(Z)^(2)=(24xx9)=216 ev`
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Find the quantum of the excited state of electrons in `He^(+)` ion which on transition to first excited state emit photons of wavelengths `108.5 nm`.
Correct Answer - B `1/lambda=R_(H)Z^(2)[1/1^(2)-1/n_(2)^(2)]` `1/(108.5xx10^(-9))=1.09678xx10^(7)xx4[1/2^(2)-1/n_(2)^(2)]` This gives `n_(2)=5`
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Calculate the energy required to excited one litre of hydrogen gas at `1` atm and `298 K` to the excited state of atomic hydrogen. The energy for the
Correct Answer - B Mole of `H_(2)` present in one litre `=(PV)/(RT)=(1xx1)/(0.0821xx298)=0.0409` Thus, energy needed to break H-H bonds in `0.0409` mole `H_(2)=0.0409xx436=17.83 kJ`. Also energy needed to excite one H...
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Electrons in a sample of H-atoms make transition from state n = y to some lower excited state. The emission spectrum from the sample is found to conta
Correct Answer - 8 `(3)/(4)xx0.85ev=13.6xx1^(2)[(1)/(n^(2))-(1)/(y^(2))]" "thereforen=4,y=8`
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A hydrogen like atom (atomic number = Z) is in higher excited state of quantum number n. This excited atom can make a transition to first excited stat
Correct Answer - `n = 7 ; Z = 3`
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An electron in an excited hydrogen atom makes transition from a state of quantum number n to a state of quantum number `(n – 1)`. (a) Show that the fr
Correct Answer - (b) The two are same
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Absorption spectrum is obtained for a sample of gas having atomic hydrogen in ground state. Which lines of the spectrum will be in the range `94 nm` t
Correct Answer - `94.7 nm, 96.9 nm, 102.2 nm, 121 nm`
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