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Grade 12Physical Chemistry

an electron is a hydrogen atom in its ground state absorbs 1.50 times as much energy as the minimum required for its escape from the atom.what is the wavelength of emitted electron? A)4.70 ANGSTROM B)4.70 NANOMETER C)9.4 ANGSTROM D)9.40 NANOMETER

Profile image of DEEPANKAR  TULSIANI
16 Years agoGrade 12
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7 Answers

Profile image of askiitian.expert- chandra sekhar
16 Years ago
Hi Deepankar, Energy required for the electron to escape is 13.6 eV Excess energy that electron have is 0.5*13.6=6.8 eV 6.8 * 1.6 *10^-19 J = h c/wavelength but the answers are not matching... there might may be some mistake... check it out
Profile image of nishchith
11 Years ago
excess energy = 6.8 eV = 6.8 * 1.6 * 10^-19 J = 1.09 * 10^-18 J
h/mc = wavelength
here it can also be written as wavelength = h/sqrt(2mKE)
where h = 6.626 * 10^-34
m = 9.1 * 10^-31 kg
KE = eV = 1.09 * 10^-18 J
so substitute these answers and the right answer is 4.7 angstrom. 
 
Profile image of nishchith
11 Years ago
excess energy = 6.8 eV = 6.8 * 1.6 * 10^-19 J = 1.09 * 10^-18 J
h/mc = wavelength
here it can also be written as wavelength = h/sqrt(2mKE)
where h = 6.626 * 10^-34
m = 9.1 * 10^-31 kg
KE = eV = 1.09 * 10^-18 J
so substitute these answers and the right answer is 4.7 angstrom. 
 
Profile image of Heet Surana
9 Years ago
Energy required for the electron to escape is 13.6 eV Excess energy that electron have is 0.5*13.6=6.8 eV 6.8 * 1.6 *10^-19 J = h c/wavelength but the answers are not matching... there might may be some mistake... check it out
Profile image of Ankit
8 Years ago
Excess energy = 13.6×.5 =6.8And lambda = square root of 150 / V A° where V is the potential difference supplied to electron So lambda = square. Rt 150/6.8 that gives lambda = 4.71 A°
Profile image of Alankrita Singh
7 Years ago
 wavelength=12.27A°/√V 
So  V=13.6×1.5×1.6×10^-19
 Wavelength=4.7A° .........................................................
Profile image of ankit singh
5 Years ago
he energy given to electron is 13.6×1.5 = 20.4eV. So the kinetic energy of emitted electron is = 20.4-13.6 = 6.8eV. The wavelength of wave associated with electron moving with kinetic energy N eV is, (12.27) / (N^1/2) angstrom. 12.27/ (6.8)^1/2 = 4.7 angstrom.