Energy of an electron is givem by `E = - 2.178 xx 10^-18 J ((Z^2)/(n^2))`. Wavelength of light required to excited an electron in an hydrogen atom from level `n = 1` to `n = 2` will be
`(h = 6.62 xx 10^-34 Js` and `c = 3.0 xx 10^8 ms^-1`).

Options

A. `1.214xx10^(-7) m`
B. `2.816xx10^(-7) m`
C. `6.500xx10^(-7) m`
D. `8.500xx10^(-7) m`

Answer

1

Explanation

`DeltaE=2.178xx10^(-18)(1/1^(2)-1/2^(2))=(hC)/lambda`
`2.178xx10^(-18)(1/1^(2)-1/2^(2))=(6.62xx10^(-34)xx3.0xx10^(8))/(lambda)" " :. lambda~~1.214xx10^(-7)m`