please I need help with this. what is the difference between molality, normality and molarity?

Question

and adhesive forces and cohesive forces? I am very confused. please help thanks

Answer 1

molality = # moles/kg solvent = m.
molarity = # mols/L of solution = M.
normality = # equivalents/L of solution = N.

Adhesive forces are those between different atoms. Cohesive forces are those forces between the same kind of atom. For example, if you notice water in a capillary tube tends to curve upward on the glass surface. Those are adhesive forces between the glass and the water molecules. Water wets the glass. If you have used a buret the meniscus is the U shaped water line and adhesive forces are responsible. If you placed liquid mercury in a capillary tube, the curvature is the opposite. That is, the mercury forms an upside down U (I can't type one like that) and that is because the cohesive forces between the mercury atoms is strong and mercury does NOT wet the glass (the adhesive forces are weak). Look up cohesive and adhesive in a dictionary. It may give a better definition. Do you know how I remember them? I think of adhesive tape that I put on my son when he was a baby and had a cut or a scrape. Adhesive tape sticks to the skin and that is a bond between two different kinds of atoms/molecules. Then, of course, cohesive must be the opposite. I hope this helps.

Answer 2

thanks