Water decomposes to hydrogen and oxygen gas as shown in the following reaction:
2H20 (g) → 2H2 (g) + O2 (g)
Given a 6.80 g sample of H20 (MM = 18.0 g/mol), how many
grams of oxygen (MM = 32.0 g/mol) is produced, assuming the
decomposition goes to completion?

Which theory was contradicted by experiments with the photoelectric effect? light spreads out after it passes through a small opening. as soon as light strikes metal, electrons will be ejected. visible light, regardless of color, will cause the ejection of electrons when striking metal. the kinetic energy of ejected electrons depends on the frequency of light that strikes the metal.