Dissolution vs Disintegration
Substances are held together by intra-molecular and intermolecular interactions. These forces have varying strengths. Dissolution and disintegration are two processes where these molecular interactions can be disturbed and sometimes new interactions are formed.
Dissolution is the process of dissolving a substance in a solvent. This substance can be in solid, gas or liquid phase. The outcome of dissolution is a solvent. The components of a solution are mainly of two types, solutes and the solvent. Solvent dissolves the solutes and form a uniform solution. So, normally solvent amount is higher than the solute quantity. When dissolving, the solute is broken down into molecular, atomic, or ionic level, and those species disperse in the solvent. All the particles in a solution have the size of a molecule or an ion, so they cannot be observed by the naked eye. The solutions can have a color if the solvent or the solutes can absorb visible light. However, solutions are typically transparent. Solvents can be in a liquid, gaseous or solid state. Most common solvents are liquids. Among liquids, water is considered as a universal solvent, because it can dissolve many substances than any other solvent. Gas, solid or any other liquid solute can be dissolved in liquid solvents. In gas solvents, only gas solutes can be dissolved. There is a limit to the amount of solutes that can be added to a certain amount of solvent.
For the dissolution to take place, the solute and the solvent substances should be compatible. We say this as “like dissolves like.” This means; if a compound to be soluble in one medium, that medium should be like the solute. For example, polar solutes dissolve in polar medium but not in a non-polar medium and vice versa. The dissolution rate and the amount of solutes which can be dissolved are governed by the solubility. Solubility constant gives the idea of how much solid can be dissolved and goes to the solution phase in equilibrium. Dissolution is a kinetic process, and for a substance to be dissolved, the overall free energy should be negative. Dissolution rate depends on various other factors too. For example, stirring, shaking, heating, cooling are some of the ways we can increase or decrease the dissolution rate. Some substances readily dissolve whereas some substances are not. For example, ionic compounds dissolve very rapidly in water, whereas starch is minutely soluble.
Dissolution is very important to maintain the balance in nature. We use dissolution principals to check on the quality of substances, in the pharmaceutical industry.
Disintegration means breaking down to small fragments, molecules or particles. In chemistry, compounds disintegrate during reactions. Or else they can be disintegrated when dissolving. Radioactive decay is another form of disintegration where radioactive elements undergo a chain of decay reactions, and ultimately they are converted to another component.
What is the difference between Dissolution and Disintegration?
• Dissolution is the process of dissolving a substance in a solvent. Disintegration means breaking down to small fragments, molecules or particles.
• Since the solute is breaking down into smaller particles (not all the instances) in dissolution, dissolution is also a disintegration process.