In the modern quantum-based atomic theory, what is the name given to a particular space around the nucleus in which an electron moves?

According to each substances heat of fusion, which of the items below requires more heat to be added per gram of substance to go from solid to liquid? silver sulfur water lead

How much would the freezing point of water decrease if 4 mol of sugar were added to 1 kg of water(k=1.86 c/mol/kg for water and i=1 for sugar

Define the kinetic molecular theory