Photons of minimum energy `496k,J. mol^(-1)` are needed to an atoms. Calculate the lowest frequency of light that will ionize a sodium atom.

Options

A. `1.24xx10^(14)s^(-1)`
B. `1.24xx10^(15)s^(-1)`
C. `2.48xx10^(15)s^(-1)`
D. `2.48xx10^(14)s^(-1)`

Answer

2

Explanation

`Na(g)+496kJ mol^(-1)rarr Na^(+)(g)`
For one photon `:E=(496kJ mol^(-1))/(N_(A)mol^(-1))=hv`
`v=((496kJ mol^(-1))((10^(3)J)/(1kJ)))/((6.63xx10^(-34)Js)(6.022xx10^(23)mol^(-1)))=1.24xx10^(15)s^(-1)(Hz)`