If a photon dropping from the n = 7 to the n = 1 level hit the surface of Ag, what would be the wavelength of the ejected electron in inches?

366 inches

Explanation:

From;

1/λ = RH(1/nf^2 - 1/ni^2)

Given that;

nf= 1, ni= 7, RH= Rydberg constant for hydrogen

1/λ = 1.097 × 10^7(1/1^2 - 1/7^2)

1/λ = 1.097 × 10^7(1 - 0.02)

λ = 9.3 × 10^-8 m or 366 inches

"record the time to complete a chemical reaction" would most likely be part of a lab procedure.