Calculate the frequency of light emitted in an electron transition from the sixth to the second orbit of a hydrogen atom. In what region of the specturm does this frequency occur?
Correct Answer - `v=7.3xx10^(14) Hz`, visible spectrum
`DeltaE_(6 to 2)=hv rArr v=(3.022xx1.6xx10^(-19))/(6.625xx10^(-34))=7.3xx10^(14) Hz`
This frequency lies in visible spectrum.
The wavelength of the emitted photon is given by
`(1)/(lambda)=R((1)/n_(1)^(2)-(1)/(3^(2)))`
When the transition takes place n =3 to n=2, then
`(1)/(lambda)=(1.097xx10^(7))((1)/(2^(2))-(1)/(3^(3)))`
`=1.097xx10^(7)xx(4)/(36)`
`:." " lambda=(36)/(1.097xx10^(7)xx5)=6.563xx10^(-7) m`
`=6563Å`
`lambda` falsl in...
Correct Answer - B
`mv_(2)r_(2)=2((h)/(2pi))`
`:.2pir_(2)=2((h)/(mv_(2)))=2lambda_(2)`
Further `lambda=(h)/(p)`
Speed of momentum is maximum is ground state. Hence `lambda` is minimum
Correct Answer - C
In hydrogen atom electrostatic force of attraction `(F_e)` between the revolving electrons and the nucleus provides the requisite centripetal force `(F_c)` to keep them in their orbits....
Correct Answer - A
Here, `E=-13.6eV=-13.6xx1.6xx10^(-19)=-2.2xx10^(-18)J`
`E=(-e^2)/(8piepsilon_0r)`
`therefore` As orbital radius,
`r=(-e^2)/(8piepsilon_0E)=(9xx10^(9)xx(1.6xx10^(-19))^2)/(2xx(2.2xx10^(-18)))=5.3xx10^(-11)m`.
Correct Answer - `1xx10^(16) Hz`
For frequency `2.5xx10^(16) Hz, h v=hv_(o)+KE_(max)`
`:. h(2.5xx10^(16))=hv_(o)+KE_(max) ...(i)`
For frequency `4xx10^(16)` Hz,
`h(4xx10^(16))=hv_(o)+2KE_(max) ...(2)`
Multiply `eq^(n)` (1) by `2` and substract `eq^(n)` (2) from it....