an energy value of 3.313x10^-19 joules is needed to break a chemical bond. what is the wavelength of energy needed to break the bond? (the speed of light = 3.00x10^10 cm/sec; planck's constant = 6.636x10^-34 J . sec

is there a formula i'm missing?

Formula (memorize this)

Energy = frequency * plancks constant.

find the frequency, then (memorize this)

frequency*wavelength= speedlight

The formula you need is the Einstein photoelectric effect equation;

h c/(wavelength) = Energy required

In this case, the equation is applied to radiative chemical dissociation, or "photolysis".

They have given you c (the light speed) and h (Planck's constant). Solve for the wavelength

thanks so much, that one really confused me.