chemistry
posted by adriana .
A H atom absorbs a photon with a wavelength of 9.50 × 10^1 nm. If the energy of the final state of the H atom was 8.72 × 10^(20) J, calculate the energy of the initial state. Express answer in scientific notation

delta E = hc/wavelength; solve for delta E.
delta E = E1E2
dE = Efinal  Einitial
Solve for Einitial.