How is oxygen different from the other four elements in group 16?

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.

Draw a line graph showing the relationship between temperature in kelvin as a function of kinetic energy.

What is a difference between a mixture of elements and a mixture of compounds