Excited atoms emit radiations consisting of only certain discrete frequencise or wavelengths. In spectroscopy it is often more convenient to use freuquencies and wave numbers are proportional ot energy and spectroscopy involves transitions between different energy levels . The line spectrum shown by a single electron excited atom (a finger print of an atom) can be given as `1/(lambda)=barvR_(H).Z^(2)[(1)/(n_(1)^(2))-(1)/(n_(2)^(2))]` where Z is atomic number of single electron atom and `n_(1),n_(2)` are integers and if `n_(2)gt n_(1),` then emission spectrum is noticed and if `n_(2)ltn_(1),` then absorption spectrum is noticed. Every line in spectrum can be represented as a difference of two terms `(R_(H)Z^(2))/(n_(1)^(2)) "and"(R_(H)Z^(2))/(n_(2)^(2)).` H-atoms in ground state (13.6 eV) are excited by monochromatic radiations of photon of energy 12.09 eV. The number of different spectral lines emitted in H-atoms will be:A. 1B. 2C. 3D. 6

Excited atoms emit radiations consisting of only certain discrete freq

1.	Excited atoms emit radiations consisting of only certain discrete frequencise or wavelengths. In spectroscopy it is often more convenient to use freuquencies and wave numbers are proportional ot energy and spectroscopy involves transitions between different energy levels . The line spectrum shown by a single electron excited atom (a finger print of an atom) can be given as `1/(lambda)=barvR_(H).Z^(2)[(1)/(n_(1)^(2))-(1)/(n_(2)^(2))]` where Z is atomic number of single electron atom and `n_(1),n_(2)` are integers and if `n_(2)gt n_(1),` then emission spectrum is noticed and if `n_(2)ltn_(1),` then absorption spectrum is noticed. Every line in spectrum can be represented as a difference of two terms `(R_(H)Z^(2))/(n_(1)^(2)) "and"(R_(H)Z^(2))/(n_(2)^(2)).` H-atoms in ground state (13.6 eV) are excited by monochromatic radiations of photon of energy 12.09 eV. The number of different spectral lines emitted in H-atoms will be:A. 1B. 2C. 3D. 6
Answer» Correct Answer - c

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