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Galvanizing

Galvanizing is the coating of a metal with a more reactive metal to stop corrosion. Normally zinc is used to coat iron. The zinc coating corrodes instead of the iron, stopping the iron from corroding. Even if the zinc is scratched, it does not co ...

                                               

Gel electrophoresis

Gel electrophoresis is a technique used to separate mixtures like DNA and proteins. The separation is based on how positively or how negatively charged a molecule is, and its size. Gel electrophoresis uses a gel and an electric field is put throu ...

                                               

Heavy metals

Heavy metals are metals or chemical compounds containing metals with relatively high density, high atomic weights, or atomic numbers. This might mean up to 96 out of the 118 known chemical elements. Mercury, lead and bismuth are examples. The ter ...

                                               

Hydration

Hydration is the adding of water molecules to a chemical substance. The anhydrous form and the hydrated form can be quite different. The hydrated form is called a "hydrate". For example, anhydrous tin chloride is a liquid, while the pentahydrate ...

                                               

Hydride

A hydride is a compound with hydrogen bonded to other elements. Except for a few of the Noble gases, all of the elements in the periodic table can form hydrides. The properties of hydrides can be very different, but some of the hydrides have simi ...

                                               

Hydrogenation

Hydrogenation is the process of adding hydrogen to organic compounds. It is done to alkenes. Vegetable oils have alkenes in them. Alkenes are liquid and spoil easily. People making shortening add hydrogen to the alkene, turning it into an alkane. ...

                                               

Hydrolysis

Hydrolysis is a chemical reaction or process where a chemical compound reacts with water. This is the type of reaction that is used to break down polymers into many smaller units. In this reaction, water is always added to the chemical compound.

                                               

Hydroxide

Hydroxide in chemistry is a name given to the diatomic anion OH −, made up of oxygen and hydrogen atoms. Most chemical compounds that contain hydroxides are bases. An Arrhenius base is a substance that when dissolved in an aqueous solution, it pr ...

                                               

IC50

The IC 50 is a measure of how effective a drug is. It indicates how much of a particular drug or other substance is needed to inhibit a given biological process by half. In other words, it is the half minimal inhibitory concentration of a substan ...

                                               

Ideal gas

An ideal gas is a gas with particular characteristics. The particles have no volume The particles neither attract each other nor repel All collisions between particles are elastic collisions and lose no kinetic energy They have random movement Id ...

                                               

Impurity

Something that has impurity is not pure. For example, water that is clean would be called pure water. Water that is dirty would be called impure water. This may result in a change in melting point or boiling point.

                                               

Infrared

Infrared radiation is a type of electromagnetic radiation. The wave is longer than light which humans can see and shorter than microwaves. The word infrared means below red. It comes from the Latin word infra and the English word red. Red light h ...

                                               

Intermolecular force

In physics, chemistry, and biology, intermolecular forces are forces that act between stable molecules or between functional groups of macromolecules. These forces are generally much weaker than the chemical bonding forces. Their bonding energies ...

                                               

Ion

An ion is an electrically charged atom or group of atoms. It can be made from an atom, or from a group of atoms. It is "charged" so it will move near electricity. This is because atoms are made of three smaller parts: equal number of negatively-c ...

                                               

Ion exchange chromatography

Ion exchange chromatography is a process in chromatography that separates ions and polar molecules based on their attraction to the ion exchanger. It works on almost any kind of charged molecule - including large proteins, small nucleotides, and ...

                                               

Ionic compound

In chemistry, an ionic compound is a compound made of ions. They have strong ionic bonds between particles. Lots of energy is required to break the bond apart, resulting in high melting and boiling points. The ions join together because they have ...

                                               

Ionization energy

Ionization energy is the energy needed to remove the most loosely attached electron from an atom. The atom is not connected to any other atoms. The chemical elements to the left of the periodic table have a much lower ionization energy. The ones ...

                                               

Isotope

The atoms of a chemical element can exist in different types. These are called isotopes. They have the same number of protons, but different numbers of neutrons. Different isotopes of the same element have different masses. Mass is the word for h ...

                                               

Isotope electrochemistry

Isotope electrochemistry is a field within electrochemistry concerned with various topics like electrochemical separation of isotopes, electrochemical estimation of isotopic exchange equilibrium constants, electrochemical kinetic isotope effect, ...

                                               

Lanthanide

A lanthanide is one of a group of 15 elements that have atomic numbers 57 to 71. This is also known as the lanthanide series or lanthanoid series. This group starts at lanthanum and it ends at lutetium. All lanthanoids are f-block elements, meani ...

                                               

Lipid

A lipid is a type of organic molecule found in living things. It is oily or waxy. Fats are made from lipid molecules. Sources of lipid can be found in algae, seeds, meat, cheese, butter and fish. Lipids are long chains of carbon and hydrogen mole ...

                                               

Litmus paper

Litmus paper is a mixture which is made from different dyes which can be taken from lichens. It is water-soluble. It is used to tell whether a solution is an acid or an alkali. Litmus paper is put onto filter paper. The paper can then be used to ...

                                               

Maillard reaction

The Maillard reaction is a chemical reaction between an amino acid and a reducing sugar that gives browned food its distinctive flavor. Seared steaks, pan-fried dumplings, cookies and other kinds of biscuits, breads, toasted marshmallows, as well ...

                                               

Mass number

The mass number of an atom is the sum of the number of protons and the number of neutrons in the nucleus. The mass number is different for each isotope of a chemical element. We write a mass number after an elements name or as a superscript to th ...

                                               

Melting point

The melting point of a substance is the temperature at which this substance goes from the solid state to the liquid one, at a normal pressure. For water, this is 0° Celsius. The chemical element with the highest melting point is tungsten. Some ch ...

                                               

Metallurgy

Metallurgy is the study of metals. Alloys are also studied. There are two main branches of Metallurgy. They are physical and chemical metallurgy. A Metallurgist is individual who researches, manufactures and develops metal items that range from c ...

                                               

Mixture

In chemistry, a mixture is a substance that is made up of two or more simpler substances. These substances can be chemical elements or compounds. A mixture can be made of liquids, solids, or gases. A mixture is not the same as a compound which is ...

                                               

Mole (unit)

Mole is the SI unit used to measure how many molecules or atoms there are. One mole is around 600 sextillion molecules. Scientists use this number because 1 gram of hydrogen is around 1 mole of atoms. The exact value of one mole is 6.022 140 78 × ...

                                               

Molecule

A molecule is the smallest amount of a chemical substance that can exist. If a molecule were split into smaller pieces, it would be a different substance. Molecules are made up of atoms that are stuck together in a particular shape or form. Not a ...

                                               

Nernst equation

Nernst Equation is a scientific equation used to find the reduction potential or voltage of an electrochemical cell. It is widely used in cell physiology and neurobiology. It is named after Walther Nernst. He was a German chemist who created this ...

                                               

Nitrocellulose

Nitrocellulose catches fire quickly. It is formed by nitrating cellulose through exposure to nitric acid or another powerful nitrating agent. When used as a propellant or low-order explosive, it is also known as guncotton. Nitrocellulose can be p ...

                                               

NMR spectroscopy

NMR spectroscopy is a type of spectroscopy that allows chemists to see the structure of a molecule. Certain atoms nuclei have certain magnetic properties when placed in a strong magnetic field. Atoms like carbon, hydrogen, and fluorine can be det ...

                                               

Noble gas compound

A noble gas compound is a chemical compound that has an element from Group 18 of the periodic table in them. Group 18 contains all the noble gases.

                                               

Octet rule

The octet rule is a general rule of thumb that applies to most atoms. It states that every atom might want to have eight valence electrons in its outermost electron shell.

                                               

Odor

An odor or odour is a volatilized chemical compound, usually at a very low concentration, which humans and other animals perceive by the sense of olfaction. Odors are also called smells, which can be used to describe both pleasant and unpleasant ...

                                               

Organic chemistry

Organic chemistry is the study of chemical compounds that contain carbon. Carbon has the ability to form a chemical bond with a wide variety of chemical elements and other carbon atoms. This allows a nearly unlimited number of combinations, calle ...

                                               

Organic matter

Organic matter is matter that has come from a recently living organism. It is capable of decay, or is the product of decay; or is composed of organic compounds. There is not one definition of organic matter only. It varies upon the context, the s ...

                                               

Oxidizing agent

Oxidizing agent can have two meanings. It can be a chemical that releases oxygen atoms. For example, potassium chlorate has a chemical formula of KClO 3. When it oxidizes a reducing agent, such as powdered aluminium metal, it loses its oxygen to ...

                                               

Ozone

Ozone, or trioxygen, is a chemical with the symbol O 3. This means one molecule of ozone is made of three oxygen atoms. Ozone is rarely called trioxygen, even though this is its IUPAC systematic name. Ozone is formed from oxygen gas by the action ...

                                               

Paraffin

In chemistry, paraffin is the common name for the alkane hydrocarbons with the general formula C n H 2 n +2. Paraffin wax refers to the solids with n between 20 and 40, inclusive. The simplest paraffin molecule is that of methane, CH 4, a gas at ...

                                               

Particle

A particle is a tiny bit of matter that makes up everything in the universe. In particle physics, an elementary particle is a particle which cannot be split up into smaller pieces. There are many different types of particles, with different parti ...

                                               

Particle size (general)

The term particle size is used to compare dimensions of different small material objects. Larger objects are usually called stone, rock, a piece of something, etc. The term particle indicates small size, usually less than centimeter. Particle mig ...

                                               

Period (periodic table)

A period in the periodic table is any horizontal row of elements. Each elements in the same period has one more proton than the one to its left. This means its atomic number is one number higher. The elements in the same period are very metallic ...

                                               

Petrochemical

A petrochemical is a chemical product that is made from petroleum, natural gas or other hydrocarbons. Some petrochemicals include alcohol, antiseptics, artificial rubber, detergents, drugs, explosives, food additives, insecticides, perfume, plast ...

                                               

Petroleum product

A petroleum product is an organic compound made in oil refineries. They result from refining crude oil into more useful products. Well-known petroleum products include: fuels Diesel fuel Liquefied Petroleum Gas LPG Kerosene fuel oil Gasoline Para ...

                                               

PH

pH is a scale of acidity from 0 to 14. It tells how acidic or alkaline a substance is. More acidic solutions have lower pH. More alkaline solutions have higher pH. Substances that arent acidic or alkaline usually have a pH of 7. Acids have a pH t ...

                                               

Photocatalysis

Photocatalysis is using light as a catalyst to increase the rate of a photoreaction. Most known photoreactions begin when light creates a free radical in the reaction system. Light can have a lot of energy and is able to break chemical bonds. For ...

                                               

Photochemistry

Photochemistry is the study of chemical reactions that go with light. There are many natural examples of such reactions. One is photosynthesis, which is a very important process through which plants form oxygen from carbon dioxide and water. Anot ...

                                               

Photodissociation

Photodissociation, photolysis, or photodecomposition is a chemical reaction in which a chemical compound is broken down by photons. One or more photons interact with the target molecule. Photodissociation is not limited to visible light. Any phot ...

                                               

Physical change

A physical change is a type of change in which the form of matter is altered but one substance is not transformed into another. The size or shape of matter may be changed, but no chemical reaction occurs. All physical changes are reversible and t ...