How do I do this? If a spot travels 2.3 cm during paper chromatography while the mobile phase travels 6.6 cm, what is the Rf value of the substance in the spot? Show all work and round to the correct number of significant figures. (Rf= distance the substance moves/distance the solvent moves)

Melting and boiling are endothermic processes. this means that these processes absorb energy from their surroundings in order to occur. use this information and the data you collected in the phase change gizmo to describe what happens to the temperature of water when you boil it, then explain why this result occurs.

Which of these expressions are correct variations of the combined gas law? p1v1t2 = p2v2t1 both

Answer asap need it by wednesday morning calculate the ph of 0.02m hcl best answer will be brainliest