What is the process of Crystallisation, Distillation, Sublimation, Fractional distillation & Chromatography
The Component Particles Of The Substance
Molecule
A molecule is a chemical compound consisting of two or more atoms joined together by chemical bonds. The term "molecule" is derived from the Latin word "moles" which means "mass" Molecules can be composed of a single type of atom (e.g. oxygen, O2) or of several types of atoms (e.g. water, H2O).
The composition of a molecule determines its chemical and physical properties. Water molecules, for example, are composed of two hydrogen atoms and one oxygen atom, and this particular combination gives water its unique properties such as high boiling point and the ability to dissolve many substances.
In addition to molecular structure, the size of a molecule also plays an important role in determining its properties. For example, larger molecules usually have a higher boiling point than smaller molecules.
In summary, molecules are the building blocks of all matter and play a crucial role in determining the chemical and physical properties of substances. The composition, structure and size of molecules all contribute to their unique properties and behavior.
Types Of Molecule
Molecules can be classified into different types based on their structure, bonding, and composition. The main types of molecules include:
Covalent molecules: Covalent molecules consist of two or more atoms held together by covalent bonds. In covalent bonds, electrons are exchanged between atoms, resulting in a strong and stable bond. Examples of covalent molecules are water (H2O), carbon dioxide (CO2) and methane (CH4).
Ionic molecules: Ionic molecules are composed of ions, which are atoms that have gained or lost electrons. Ionic bonds are formed when one atom donates electrons to another atom, forming positive and negative ions. These ions are held together by the electrostatic attraction between the positive and negative charges. Examples of ionic molecules are common salt (NaCl) and magnesium oxide (MgO).
Polar molecules: Polar molecules are covalent molecules in which the electrons are not evenly distributed between the atoms. This causes a molecule to have a positive end and a negative end, making it polar. Polar molecules can interact with other polar molecules through dipole-dipole interactions, in which the positive and negative ends of the molecules attract. Examples of polar molecules are water (H2O) and acetic acid (CH3COOH).
Nonpolar molecules: Nonpolar molecules are covalent molecules in which the electrons are evenly distributed among the atoms. This results in a symmetrical molecule that has neither a positive nor a negative end. Nonpolar molecules do not interact with other polar molecules and are usually hydrophobic, meaning that they do not mix well with water. Examples of nonpolar molecules are hydrocarbons such as ethane (C2H6) and methane (CH4).
Inorganic molecules: Inorganic molecules are molecules that do not contain carbon and do not come from living organisms. Examples of inorganic molecules are minerals, salts, and acids.
Organic molecules: Organic molecules are molecules that contain carbon and come from living organisms. Organic molecules can be classified into different types based on their functional groups, such as alcohols, carbonyls, and amines. Examples of organic molecules are sugars, lipids and proteins.
In summary, there are different types of molecules based on their structure, bonding, and composition. Understanding the properties and behavior of the different types of molecules is critical in the fields of chemistry and biology and has important applications in areas such as medicine, agriculture, and materials science.
Atom
An atom is the basic unit of matter and the defining structure of the elements. The term "atom" comes from the Greek and means " indivisible", because it was once thought that atoms were the smallest things in the universe and could not be divided.
Atoms consist of a nucleus containing protons and neutrons surrounded by electrons orbiting the nucleus. Protons have a positive charge, electrons have a negative charge, and neutrons have no charge. The number of protons in the nucleus of an atom determines which element it is; for example, all hydrogen atoms have one proton, all helium atoms have two, and so on.
Atoms can combine to form molecules that make up the substances we encounter in everyday life, such as water, air, and solid objects. They can also combine to form more complex structures, such as cells and organisms.
In summary, atoms are the building blocks of matter and there are different types (elements) with different numbers of protons in the nucleus that determine their chemical and physical properties.
Separation Of Mixture
Process Of Crystallisation
Crystallization is the process of forming solid crystals from a liquid or dissolved solid. It occurs when the molecules in a solution arrange themselves in an ordered, repeating pattern that forms a solid. This process takes place when the dissolved molecules in a solution become more organized and combine to form a solid.
The process of crystallization involves several steps, including:
Supersaturation: The first step in crystallization is to create a solution that is supersaturated, meaning it contains a higher concentration of solutes than is normally possible at a given temperature and pressure.
Nucleation: Once a solution is supersaturated, the next step is to form tiny seed crystals called nuclei. These nuclei serve as a starting point for the growth of the crystal structure.
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Growth: The nuclei then serve as a center for the solute molecules to form the repeating pattern that characterizes a crystal. This pattern repeats and grows larger as more solute molecules organize and join the crystal structure.
Precipitation: the final step in crystallization is precipitation, which is the process of removing the solid crystals from solution. This is usually done by cooling the solution or by adding a precipitant, a chemical that causes the solute to leave the solution and form solid crystals.
Crystallization is a widely used process in many industries, such as pharmaceuticals, food manufacturing, and mineral extraction. In the pharmaceutical industry, for example, it is used to purify drugs and to produce crystalline forms of active ingredients that have specific properties such as solubility and stability.
In summary, crystallization is a process in which solid crystals are formed from a liquid or dissolved solid by creating a supersaturated solution, nucleation, growth and precipitation of the solid crystal.
Process Of Distillation
Distillation is a process for separating the components of a mixture based on their boiling points. It is commonly used to purify liquids such as water and alcohol by heating the mixture to boiling and collecting the resulting vapors. These vapors are then condensed back into a liquid form, resulting in a purified substance.
Distillation takes place in a still, a vessel in which the mixture is broken down into its individual components. The mixture is heated to its boiling point, and the resulting vapor contains a higher concentration of the component with the lowest boiling point. This vapor is then cooled and condenses back into a liquid form that can be collected and separated from the other components.
To achieve maximum separation of the components, the process can be repeated several times, using the purified liquid as feedstock for the next distillation. In addition, the distillation unit may be equipped with a series of trays or plates, each optimized for collecting a particular component of the mixture.
Overall, distillation is a versatile and effective process for purifying liquids that has applications in numerous industries, including petrochemical, pharmaceutical, and food and beverage.
Process Of Sublimation
Sublimation is a phase transition process in which a solid substance passes directly to a gaseous state, bypassing the intermediate liquid state. This process occurs when the pressure and temperature of the substance reach a point where the energy of the solid particles is sufficient to break their bonds and allow them to pass directly to the gaseous state. Sublimation is often observed in solids such as ice, dry ice, and certain types of ink used in printers.
For sublimation to occur, the substance must have a sufficiently low boiling point and a sufficiently high vapor pressure. The rate of sublimation is influenced by several factors, including temperature, pressure, and surface area.
Sublimation is a unique process that has many applications, including freeze-drying in the food industry, preserving biological samples, and producing high-quality printed images in digital printing. In addition, sublimation can be used as a method for cleaning solid materials by removing impurities trapped in the solid state and transferring them to the gaseous state where they can be easily removed.
Process Of Fractional Distillation
Fractional distillation is a process for separating a liquid mixture into its individual components based on their boiling points. In this process, the mixture is heated to produce vapor, which is then cooled and condensed back to a liquid. The condensate is collected in a series of trays or fractionating columns, each tray collecting a fraction of the condensate with a specific boiling point range. This is repeated until all components of the mixture are separated.
The fractional distillation process is based on the fact that the different components of a mixture have different boiling points and therefore vaporize at different temperatures. When the mixture is heated, the components with lower boiling points evaporate first, while the components with higher boiling points remain in a liquid state. The vapor is then passed through a fractionation column where it is cooled and condensed back to a liquid. The fractionation column contains a series of trays at different temperatures where the components of the mixture condense and separate according to their boiling points. The resulting fractions can then be collected for further use or analysis.
Fractional distillation is widely used in the chemical, petrochemical and pharmaceutical industries for the separation and purification of various substances. It is also used in the production of alcoholic beverages to separate ethanol from water and other impurities.
Process Of Chromatography
Chromatography is a chemical separation process in which the components of a mixture are separated based on their individual physical and chemical properties. The process usually involves a stationary phase, which does not move, and a mobile phase, which is a liquid or gas that moves through the stationary phase. The stationary phase may be a solid, e.g., silica gel, or a liquid, e.g., cellulose, adsorbed on a solid support, and the mobile phase may be a liquid, e.g., water, or a gas, e.g., air.
When a mixture is applied to the stationary phase, the components of the mixture interact with the stationary phase and the mobile phase, resulting in their separation based on their unique properties. For example, in liquid chromatography, the components of the mixture move through the stationary phase at different rates depending on their solubility in the mobile phase and their interaction with the stationary phase. In gas chromatography, the components of the mixture move through the stationary phase based on their volatility and their interactions with the stationary phase.
After the components are separated, they can be further analyzed by various methods, such as spectroscopy, to determine their identity and quantify their amount. Chromatography is widely used in various fields such as biochemistry, environmental analysis, and forensic analysis, and has numerous applications, including the analysis of complex mixtures, purification of compounds, and identification of unknown substances.
Process Of Steam Distillation
Steam distillation is a chemical separation process that separates compounds based on their boiling points and volatility. It is used to separate compounds that have low boiling points and are not volatile enough to be distilled directly.
In steam distillation, a mixture of compounds is heated in a distillation flask and steam is introduced into the flask. The steam rises, entraining the volatile components of the mixture and separating them from the less volatile components. The vapor then condenses back to a liquid and is collected, creating two separate layers. The less volatile components remain in the distillation flask, while the more volatile components are collected in the condenser.
Steam distillation is widely used in the essential oil industry, as well as in the isolation of fragrances from plants, such as herbs and spices, and in the extraction of aromatic compounds from plants. In addition, steam distillation is also used to separate some organic compounds, such as alcohols and esters, that are not volatile enough to be distilled directly.