How many calcium ions are in 0.5 mol of cacl2?

Which element would mostly likely have an electron affinity measuring closest to zero

Areaction is first order with respect to reactant x and second order with respect to reactant y. which statement describes the rate law for this reaction?

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.