sulfate melting point
The melting point of a substance is the temperature at which the solid and liquid forms of a pure substance can exist in equilibrium. The melting point can be measured by applying heat to a sample and watching the temperature rise until the solid is converted into a liquid with no change in temperature.
Sulfates have many uses and are used in the chemical industry, as well as biological systems such as algae and microorganisms. Examples of sulfates include magnesium sulfate, Epsom salts, and gypsum.
Sodium sulfate is a cheap and widely used material in the chemical industry for manufacturing synthetic detergents and soaps, as well as a laboratory reagent. It may also be used to enhance the irritant action of certain detergents.
Synthetic sulfates are often used in the manufacture of perfumes and cosmetics. They are also used to produce heat storages and glass.
A crystalline substance that is not pure will usually melt at a much lower temperature than a pristine substance. This behavior is called melting point depression and can be a useful tool in determining purity of a crystalline compound.
Several techniques are available to determine the melting point of a substance, including Thiele’s tube and a Kofler bench. A metal strip is kept at a specific temperature range (usually from room to 300degC) and the solid whose melting point is being determined is placed on this strip.
Optical properties can also be used to measure the melting point of a solid. Powdered crystalline substances are opaque in the crystalline state but transparent when in liquid form, so the amount of light that shines through the powder when it is melted can be determined. The difference in optical properties can be recorded in a capillary tube, and compared with the measured furnace temperature to indicate the melting point of the material.