The change in direction of the light beam while passing from one medium to another medium with different intensity is called refraction.
Refractometry is a method used to make determinations such as concentration and amount of substance, using the principle that the refractive index of each medium is different. Refractive index is one of the physical properties of a substance, such as its boiling point, melting point, and density, and each substance has a specific refractive index. For this reason, it is a method that we can use in qualitative and quantitative analysis.
REFRACTIVE INDEX
The refractive index is actually a physical phenomenon, not a chemical. Every day is before our eyes. If you look at the tea glass at a 45 degree angle, you will see the teaspoon under the liquid as if it were broken. Rays passing through the water are refracted at a certain angle and the object looks as if it is in a different place. Scientists who studied this refraction of light found that not only water but all liquids refracted light and that this was a property specific to that substance, and they called it the refractive index. Glycerin, ethyl alcohol, acetone and other pure liquid substances have a unique refractive index. On the other hand, the refractive indices of liquid mixtures with more than one component are a fixed number. In other words, 5% sugar water solution has a certain refractive index. It follows from this result that the refractive index is a summable multiplicity. So for example, if you mix a liquid with a refractive index of 1 and another liquid with a refractive index of 2 in equal volumes, the refractive index of the product will be 1.5. This phenomenon is actually a serious problem for the refractive index. Because; We can mix two liquids with a refractive index of 1.5 and 0.75 and make a mixture with a refractive index of 1, but this product is definitely not water.
If the percentage of the substance dissolved in a solution is unknown, it is possible to determine it by finding the refractive index value of the substance. Refractive index is one of the physical properties of a substance, such as its boiling point, melting point, and density, and each substance has a specific refractive index. The change in direction of light while passing through different media is called refraction, and the ratio of the speed of light in a vacuum to its speed in matter is called the refractive index. The refractive index of each medium is different.