The blank is the temperature at which a material changes from a liquid to a gas while the blank is the temperature at which a material changes from a solid to a liquid

Which of the following signs of a chemical reaction are observed in the reaction of potassium with water? precipitate formed temperature change smell produced gas produced color change

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.

When did stem cell research become known ? who discovered stem cell? what experiments or studies have been conducted so far?