The solidification It is a physical process that leads matter from a liquid state to a solid state, by altering its conditions of temperature (freezing) or pressure. For example: candle making, gelatin preparation, mercury freezing. It is the reverse process of merger.
Although solidification and freezing are terms that are used interchangeably to refer to the passage from liquid to solid of a substance, there is a detail to take into account many times, and that is that the solidification process refers mainly to the change from liquid to solid by increasing the pressure of the liquid.
Solidification goes through the following stages:
- Appearance of solid nuclei in liquid (nucleation), such as crystals or scattered hardeners in the liquid content.
- Appearance of dendrites in the fluid, that is, solid lines that unify the nuclei and show the appearance of solid or semi-solid blocks.
- Appearance of solid grains and subsequent loss of mobility of the particles, which results in solidification of the liquid.
Examples of solidification
- Ice making. By bringing water to its freezing point of 0 ° C, the liquid loses its mobility and becomes a solid state, thus forming ice in the shape of the container where the water was contained.
- Candle making. Made from paraffins derived from petroleum, they are given their characteristic shape and the wick is inserted with the wax in a more or less liquid form, due to the effect of heat. Then, as it cools, the wax hardens and remains solid until the wick is lit, since the fire restores its liquidity.
- Jewelry manufacturing. Gold, silver and other precious metals are used molten to make jewelry: rings, necklaces, etc. Once in a liquid state, the metal is allowed to cool in a specific mold, from which it will come out solid and resistant.
- Chocolate making. To make the chocolate, a powder obtained from the roasting and grinding of cocoa is used, mixed with water and milk to make a semi-liquid paste, which is then cooled and dried to acquire the specific forms of its commercialization.
- Brick making. Building bricks are made from a mixture of clays and other elements that, in a semi-liquid paste, acquire their specific shape. This mixture is then baked to remove moisture and give it solidity and resistance.
- Glass manufacturing. The production of glass containers of all kinds starts from the fusion of the raw material (silica sand, calcium carbonate and limestone), until it is given the right consistency to blow and shape it, and then cool it and allow it to obtain its characteristic hardness and transparency. .
- Tool making. From liquid steel (alloy of iron and carbon), various tools and utensils for daily use are manufactured, whose resistance to impacts, pressure and heat are important, since the fusion of steel occurs at very high temperatures ( around 1535 ° C), rarely achievable outside of industrial furnaces. The liquid steel is allowed to cool and solidify in a mold and the tool is obtained.
- Gelatin Preparation. Although it is a colloid (semisolid), obtained from a suspension of collagen from spraying and subsequent hydration of connective tissues of animal origin, it is an example of solidification by losing the heat essential to make the liquid mixture.
- Latex manufacturing. Latex is a colloidal solution of fats, waxes and resins of vegetable origin, and the most elastic material known. Its production for gloves or condoms begins with the collection of the substance and its chemical treatment to keep it liquid, its subsequent ironing and the production of very thin layers of the substance that, now, is allowed to dry and solidify.
- Gestation of igneous rocks. Igneous rocks have their origin in the volcanic magma that inhabits the deep layers of the earth’s crust, which when sprouting to the surface cools, densifies and hardens, until it becomes stone.
- Candy making. These sweets have their origin in the burning and melting of common sugar. With this procedure a brownish liquid substance is obtained that can, once poured into a mold, be allowed to harden to make a caramel.
- Mercury freeze. At minus 45 ° C, mercury, also known as liquid silver, solidifies, whose presence at room temperature is normally fluid.
- Handmade modeling of clay. Clay is a type of soil that, when hydrated, becomes malleable and allows making pots, figures and handicraft utensils. Once dehydrated, the clay hardens and solidifies, becoming a resistant material.
- Manufacture of blood sausages. Like other sausages, blood sausage is made from clotted and marinated blood, cured inside the skin of pig tripe. When coagulating, the liquid blood becomes the solid meat of the blood sausage.
- Making butter or margarine. One of the industrial manufacturing processes of these foods consists of the saturation of oils of vegetable or animal origin, that is, their hydrogenation, to convert the double bonds of the carbon chains into simple ones. Through this process, the oil becomes a solid or colloid (like butter) at room temperature.