Is melting ice cream a chemical or physical change?

Find the number of grams of hcl needed to react completely with .50 moles of magnesium.

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

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.