The wavelength of series limit for lyman series for `He^(o+)` would be

Options

A. `911.7 Å`
B. `227.9 Å`
C. `1215.1 Å`
D. `363.8 Å`

Explanation

`Z= 2 (for HE^(Theta))`
series limit for lyman series
`n_(1) =1,n_(2) = oo`
`bar v = (1)/(lambda) = RZ^(2)((1)/(n_(1)^(2)) - (1)/(n_(2)^(2))) = R(2)^(2)((1)/(1^(2)) - (1)/(oo^(2))) = 4R`
`lambda = (1)/(4R)= (1)/(4 xx 109677 cm^(-1)) `
`= 227.9 xx 10^(-10) m = 227.9Å`