According to Science Kids, things dissolve faster in hot water because the molecules in hot water move at a greater speed, bumping more frequently against the solute (the item being dissolved). The more frequent bumping against the solute causes it to dissolve quicker in the water.Know More
Hot water has a higher amount of kinetic energy. The increased amount of kinetic energy is what causes the molecules to move faster. A solvent (the item that the solute is dissolved into) dissolves the solute by breaking up both its molecular bonds and the solute's molecular bonds. The molecular bonds in both substances have to be broken so that new molecular bonds can form between the solute and solvent. Once the solvent and solute are combined with molecular bonds, it is known as a solution.
The amount of energy required to dissolve a solute into a solvent depends on what substance the solute is. Solutes with strong molecular bonds require more energy for the bonds to be broken. Weak solutes can dissolve at a lower temperature than strong solutes.
Solutes that do not dissolve in water have nonpolar covalent bonds. Nonpolar covalent bonds have a low electronegativity (tendency to attract electrons) and do not readily form new molecules. Water is a polar molecule that requires another polar molecule to form a new molecule.Learn more about Solutions & Mixtures
Salt, as well as any other soluble substance, dissolves quicker in hot water because heat makes the water molecules move faster, creating more space between them. This extra space means the salt molecules more readily make contact with the water molecules, binding to them and creating a solution.Full Answer >
The Department of Physics at the University of Illinois states that sugar dissolves faster in hot water than in cold water because hot water gives sugar crystals energy. The hotter the water, the higher the energy, and the faster sugar crystals dissolve.Full Answer >
According to the Purdue University College of Science, sugar dissolves easily in water due to the fact that sucrose molecules are held together with weak intermolecular forces. The energy produced when these molecules bond with water is more than enough to offset the energy needed to break those bonds in the first place.Full Answer >
Oil and water do not mix because the molecules in water are polar, which causes them to be attracted to other water molecules and exclude the oil molecules. When the oil molecules are excluded from the water molecules, they clump together with one another.Full Answer >