His work foreshadowed the periodic table. He tried organizing elements into triads, a set of 3 elements with similar properties. In each triad the mean of the lightest and heaviest atomic weight equaled to approximately the atomic weight of the middle element.
90 grams due to laws of conservation of mass. Output mass = input mass. Mass can never be created or destroyed.
Oil is less dense than water, so the difference would be its density. Water is a good solvent, which means It can dissolve other substances.
