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Phospholipid

Phospholipids are a type of fat that contain phosphorus. They are major parts of all cell membranes because they form lipid bilayers. Phospholipid molecules usually have hydrophobic tails and a hydrophilic head. Biological membranes in eukaryotes ...

                                               

Phosphoric acid

Phosphoric acid, also known as orthophosphoric acid, is a chemical compound. It is also an acid. Its chemical formula is H 3 PO 4. It contains hydrogen and phosphate ions. Its official IUPAC name is trihydroxidooxidophosphorus.

                                               

Phosphorous acid

It is a white solid. It absorbs water. It is a strong reducing agent. It can be deprotonated twice. When it is heated, it turns into phosphoric acid and phosphine. It is toxic. Salts of phosphorous acid is called phosphites. It reacts with mercur ...

                                               

Phosphorus(V) oxide

Phosphorus oxide, also known as phosphorus pentoxide, is a chemical compound. Its chemical formula is P 4 O 10. It contains phosphorus and oxide ions. It contains phosphorus in its +5 oxidation state.

                                               

Platinum

Platinum is a soft, heavy, white metal. It is a precious metal. It usually costs more than gold. In chemistry, platinum is element number 78, and its atoms have an atomic weight of 195 a.m.u. The symbol for platinum is Pt, from Spanish platina me ...

                                               

Plutonium

Plutonium is the chemical element with the atomic number 94 and chemical symbol Pu. It is a highly radioactive metal, and is the metal used in most nuclear weapons. The chemical element plutonium has some different isotopes. The most important is ...

                                               

Pnictogen

The Group 15 elements, also called the pnictogens, Group V elements, or Group VB elements, are a group on the periodic table. They have many different properties. Nitrogen is a colorless unreactive gas that helps us breathe. Phosphorus is a super ...

                                               

Polar bond

In chemistry, a polar bond is a type of covalent bond between two or more dissimilar atoms, in which electrons are shared unequally. A covalent bond is the "strong" kind of bond that makes a molecule. Electrons are negatively charged. If the two ...

                                               

Polonium

Polonium is a rare radioactive metalloid. It is chemical element 84 on the periodic table and its symbol is Po. It was discovered in 1898 by Marie and Pierre Curie. Polonium is highly unstable, radioactive and toxic. This makes it difficult to ha ...

                                               

Polychlorinated biphenyl

Polychlorinated biphenyls are organic chemical compounds that contain chlorine atoms. They were used in industrial chemistry, and to make certain transformers, capacitors, and cooling fluids. The Stockholm Convention on Persistent Organic Polluta ...

                                               

Polyester

Polyester is a type of man-made material. It is a synthetic polymer. With 18% market share of all plastic materials produced, it is third after polyethylene and polypropylene.

                                               

Polyethylene terephtalate

Polyethylene terephthalate is a thermoplastic polymer resin of the polyester family. The chemical industry makes it. It is used in synthetic fibers; beverage, food and other liquid containers; thermoforming applications; and engineering resins of ...

                                               

Polymerization

Polymerization or polymerisation is the process in which small molecules, called monomers, join chemically to produce a very large chain-like or network molecules, called a polymer. The monomer molecules may all be alike, or they may represent tw ...

                                               

Polypropylene

Polypropylene, or polypropene, is a type of plastic. It is a thermoplastic polymer which can be made into a fibre for yarn and fabric, film for packaging, or many other shapes. As a plastic it can be made translucent but usually is opaque and oft ...

                                               

Polytetrafluoroethylene

Teflon redirects here, other uses are at Teflon disambiguation In chemistry, Polytetrafluoroethylene is a polymer of tetrafluoroethylene. It is a fluoropolymer, because the polymerization is based on strong bonds of fluorine and carbon. Polytetra ...

                                               

Polyvinyl chloride

Polyvinyl chloride, also called Polychloroethene or PVC, is a thermoplastic. It turns soft when heated and hard when cooled. Polyvinyl chloride is made by polymerization of the monomer vinyl chloride CH 2 =CHCl. PVC can be made softer and more fl ...

                                               

Potassium

Potassium is a chemical element in the periodic table. It has the symbol K. This symbol is taken from the Latin word kalium. Potassiums atomic number is 19. It has 19 protons and electrons. Potassium is not found as an element in nature, because ...

                                               

Potassium aluminium sulfate

Potassium aluminium sulfate, or potash alum, or potassium alum, is a chemical compound. Its chemical formula is KAl 2. It contains potassium, aluminium, and sulfate ions. Crystals of it are transparent, and it is white when made into a powder.

                                               

Potassium bromide

It is a white crystalline solid. It dissolves easily in water. When it is dilute, it tastes sweet; when it is a little concentrated, it tastes bitter; when it is very concentrated, it tastes salty. This taste is because of the potassium ion.

                                               

Potassium fluoride

Potassium fluoride is a colorless crystalline solid. It rarely occurs in the ground. It dissolves easily in water. It can react with glass. Hydrofluoric acid is more effective at reacting with glass, though. It has to be stored in plastic or plat ...

                                               

Potassium iodide

It is a colorless crystalline solid. It is a weak reducing agent. It reacts with chlorine to make iodine and potassium chloride. It turns yellow when in air. This is because it reacts with oxygen and carbon dioxide to make iodine and potassium ca ...

                                               

Potassium nitrate

Potassium nitrate is a colorless solid. It dissolves in water. It is a common source of the nitrate ion. Potassium nitrate is a strong oxidizer. It decomposes to potassium nitrite and oxygen when heated. Its pH is almost neutral. It burns with a ...

                                               

Potassium sulfate

It is a white crystalline solid. It dissolves in water easily. It does not dissolve in potassium hydroxide or concentrated ethanol. It can react with additional sulfuric acid to make potassium bisulfate.

                                               

Praseodymium

Praseodymium is a chemical element that has the symbol Pr on the periodic table. It has the atomic number 59 which means it has 59 protons in an atom. It is a soft silvery metal that can be used to make yellow-green salts. It is mixed with magnes ...

                                               

Primordial nuclide

Primordial nuclides are nuclides found on Earth which have existed since before the Earth was formed. They are also called primordial isotopes. Primordial nuclides are found in the interstellar medium. They were formed in or after the Big Bang, b ...

                                               

Promethium

Promethium is a chemical element that has the symbol Pm on the periodic table. It has the atomic number 61 which means it has 61 protons in its atom. It is a Lanthanide. All its isotopes are radioactive. Together with Technetium, these are the on ...

                                               

Propene

Propene is an organic compound. The substance is also known as propylene and has the formula C 3 H 6. It is the second-simplest alkene. Since it is only made of hydrogen and carbon atoms, it is a hydrocarbon. At room temperature and normal pressu ...

                                               

Pseudoephedrine

Pseudoephedrine is a decongestant. The salts pseudoephedrine hydrochloride and pseudoephedrine sulfate are found in many over-the-counter drugs either as single-ingredient preparations, or more commonly in combination with antihistamines, paracet ...

                                               

Pyrimidine

Pyrimidines include three of the bases in DNA and RNA. A pyrimidine is an aromatic heterocyclic organic compound, similar to purine. It has nitrogens at positions 1 and 3 in the ring.

                                               

Qualitative analysis

Qualitative analysis is a field of analytical chemistry. It uses chemical reactions to find out what an unknown chemical substance is. Qualitative chemistry is used in many jobs. It is very useful for testing for drugs and poisons. Many reactions ...

                                               

Quark

A quark is a tiny particle which makes up protons and neutrons. Atoms are made of protons, neutrons and electrons. It was once thought that all three of those were fundamental particles, which cannot be broken up into anything smaller. After the ...

                                               

Radium

Radium is a chemical element with the atomic number 88 and symbol Ra on the periodic table. It was discovered by Marie Curie and Pierre Curie in the form of radium chloride in 1898. It is an almost pure-white alkaline earth metal, but when it is ...

                                               

Radon

Radon is element 86 on the periodic table. Its symbol is Rn. Radon is a gas and is part of the group known as the noble gases. It does not react with other elements, so it is found pure. Radon is radioactive, meaning that it can give off harmful ...

                                               

Receptor antagonist

A receptor antagonist is a biological repressor molecule. A receptor antagonist slows down the cell by stopping some of the cell reactions by clogging up the areas that make the cell work. They are sometimes called blockers, such as beta blockers ...

                                               

Refinery

Different types of refineries are as follows: metal refineries refining metals such as alumina, copper, gold, lead, nickel, silver, uranium, zinc, magnesium and cobalt; vegetable oil refinery natural gas processing plant, which purifies and chang ...

                                               

Refrigerant

A refrigerant is a chemical substance that is found in an air conditioner, a refrigerator, and in other refrigeration equipment. Refrigerants are chosen for the ease of converting them from liquid to vapor or vice versa, depending on their temper ...

                                               

Rust

Rust is a type of corrosion. It happens to iron and its alloys when it is exposed to air or water for a long time. Rust slowly decomposes iron into other chemicals, because of a reaction with the oxygen molecules. Both air and water are needed fo ...

                                               

Scandium

Scandium is chemical element number 21 on the periodic table. Its symbol is Sc. Scandium is a metal in a group known as the transition metals. It is also a rare earth metal. What this means is that there is not very much scandium found in the ear ...

                                               

Seaborgium

Seaborgium is a chemical element. In the past, it has been named eka-tungsten but is now named seaborgium. It has the symbol Sg. It has the atomic number 106. Seaborgium is a radioactive element that does not exist in nature. It has to be made. T ...

                                               

Selenium monochloride

Selenium monochloride, also known as selenium chloride or diselenium dichloride, is a chemical compound. Its chemical formula is Se 2 Cl 2. It contains selenium in its +1 oxidation state. It also contains chloride ions.

                                               

Shielding effect

Shielding is when an electron becomes less attracted to an atom the further it is away from the nucleus. This is because the forces holding atoms together become weaker as distance increases.

                                               

Sigma bond

A sigma bond is a type of chemical bond. It is the strongest one of the covalent type. In a sigma bond, the atomic orbitals from two atoms which are nearby go one on top of each other. This is different from a pi bond where they touch sideways. T ...

                                               

Silicon dioxide

Silicon dioxide, also known as silica, is a chemical compound, the oxide of silicon. Its chemical symbol is SiO 2. It is known for its hardness since the 16th century. It is an important compound used in most types of glass and other hard substan ...

                                               

Silver chloride

It is a white crystalline solid. It does not dissolve in water. When it is exposed to light, it turns back into silver and chlorine. It dissolves in several solutions, such as ammonia.

                                               

Silver(I) sulfide

Silver sulfide, also known as silver sulfide and silver sulphide, is a chemical compound. Its chemical formula is Ag 2 S. It contains silver in its +1 oxidation state. It also contains sulfide ions.

                                               

Slag

Slag is a liquid residue from making iron. It consists of calcium silicate. The silicon dioxide in iron has to be taken away. The calcium oxide reacts with the silicon dioxide solid to make liquid calcium silicate, which is lighter than iron. It ...

                                               

Sodium

Sodium is the chemical element number 11 in the periodic table of elements. It follows that its nucleus includes 11 protons, and 11 electrons orbit around it. Even if many isotopes can be artificially made, all decay in a short time. As a result, ...

                                               

Sodium acetate

Sodium acetate is used to reduce the effects of water damage to concrete. It does this by acting as a concrete sealant. Compared to epoxy, which is commonly used, sodium acetate is cheaper and does not damage the environment.

                                               

Sodium amide

Sodium amide, also known as sodamide, is a chemical compound. It contains sodium and amide ions. Its chemical formula is NaNH 2. It is a very strong base, even stronger than hydroxides like sodium hydroxide. It reacts violently with water. It is ...

                                               

Sodium bicarbonate

Sodium bicarbonate is baking soda, bicarb or bicarbonate of soda. It is a chemical compound, sodium hydrogen carbonate, with the formula NaHCO 3. The elements within it are sodium, hydrogen, carbon, oxygen. It is a white crystalline powder. Sodiu ...