Question

The energy required to dislodge electrons from sodium metal via the photoelectric effect is 275 kJ/mol . What wavelength of light, in nanometers, has sufficient energy per photon to dislodge an electron from the surface of sodium? Express the wavelength in nanometers to three significant figures.

Answer 1

435

Step-by-step explanation:

Answer 2

435 nm

Step-by-step explanation:

Given the energy required to dislodge electrons from sodium metal via the photoelectric effect is 275 kJ/mol

⇒ energy per photon =energy per mole/Avogadros number

=
`(275*1000)/(6.022*10^(23))`

= 4.5666 x 10^(-19) J

`Wavelength=(hc)/(energy per photon)`

=
`(6.626*10^(-34)*3*10^8)/(4.56*10^(-19))`

=
`4.35*10^(-7) m`

=435 nm

hence the wavelength is equal to 435 nm