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Sodium bromide

Sodium bromide is a white solid. It dissolves easily in water. When it is heated very strongly in air, it makes bromine gas. It also reacts with chlorine to make liquid bromine.

                                               

Sodium periodate

Sodium periodate is a chemical compound. Its chemical formula can be NaIO 4 or Na 5 IO 6. It has sodium and periodate ions in it.

                                               

Soman

Soman is the name of a nerve agent, which was developed in Germany, in 1944. NATO use the abbreviation GD for Soman. During the 1930s, and 1940s, three nerve agents were developed. The two others were Tabun and Sarin. Soman is the most stable of ...

                                               

Spontaneity (chemistry)

The spontaneity of a process refers to whether or not the reaction would occur without an input of energy, because of the value of the reactions Gibbs free energy. The Gibbs free energy is given by: Δ G = Δ H − T Δ S {\displaystyle \Delta G=\Delt ...

                                               

Strong acid

In chemistry, a strong acid is an acid which ionizes completely in a solution of water. It always loses a proton when put in water. A weak acid does not always lose a proton, though; It can lose its proton, but not all the time. They also have a ...

                                               

Strontium

Strontium is a chemical element. It has the chemical symbol Sr. It has the atomic number 38. It is a metal. The colour of the metal is silver-white or yellow-silver. The metal is soft, and highly reactive chemically. In chemistry it is placed in ...

                                               

Substitution reaction

In chemistry, a substitution reaction happens when an atom or a group of atoms is replaced by a different one. Substitution reactions can be of many different types. In organic chemistry, the main ones are nucleophilic substitution and electrophi ...

                                               

Sulfur dichloride

Sulfur dichloride, also known as sulfur chloride, is a chemical compound. Its chemical formula is SCl 2. It contains sulfur in its +2 oxidation state. It also contains chloride ions.

                                               

Taxane

Taxanes are poisonous alkaloids produced by Yew plants. Alkaloids are natural basic chemical compounds which contain nitrogen atoms. The name comes from the word alkaline and was used to describe any alkaline containing nitrogen. Alkaloids are ma ...

                                               

Tear gas

Tear gas is the name for a number of chemical compounds. They are not actually gases. They are fine powders or mists of liquid. The chemicals are acidic and cause pain in the eyes. Tear gas may cause temporary blindness for up to 45 minutes. Tear ...

                                               

Technetium

Technetium is a chemical element. It has the chemical symbol Tc. It has the atomic number 43. The color of technetium is silvery-grey. It is radioactive. It is a crystaline metal. In chemistry it is placed in a group of metal elements named the t ...

                                               

Telluric acid

Telluric acid is a chemical compound. It is an acid. Its chemical formula is H 6 TeO 6. It contains hydrogen and tellurate ions. It contains the TeO 6 6- form of the tellurate ion. Telluric acid is a weak acid. It reacts with strong bases to make ...

                                               

Tellurium trioxide

Tellurium trioxide, also known as tellurium oxide is a chemical compound. Its chemical formula is TeO 3. It contains tellurium and oxide ions. It contains tellurium in its +6 oxidation state.

                                               

Tetrahydrocannabinol

Tetrahydrocannabinol, or THC, is the chemical or drug made in the cannabis that causes a person to feel different. It is similar to at least 113 other chemicals in cannabis, known as cannabinoids, but not all of them will make you feel different ...

                                               

Tetrasulfur tetranitride

Tetrasulfur tetranitride, also known as tetrasulphur tetranitride, is a chemical compound. Its chemical formula is S 4 N 4. It contains sulfur in its +3 oxidation state. It also contains nitride ions.

                                               

Thallium halide

The thallium halides come in two oxidation states: monohalides, where thallium has the oxidation state +1, and trihalides, where thallium generally has oxidation state +3.

                                               

Thallium(I) oxide

Thallium oxide, also known as thallous oxide, is a chemical compound. Its chemical formula is Tl 2 O. It has thallium and oxide ions in it. The thallium is in its +1 oxidation state.

                                               

Thallium(III) hydroxide

Thallium hydroxide, also known as thallic hydroxide, is a chemical compound. Its chemical formula is Tl 3. It has thallium and hydroxide ions in it. The thallium is in its +3 oxidation state.

                                               

Thermoplastic

A thermoplastic is a material, usually a plastic polymer, which becomes more soft when heated and hard when cooled. Thermoplastic materials can be cooled and heated several times without any change in their chemical or mechanical properties. When ...

                                               

Thorium

Thorium is a chemical element in actinide group. It is a weakly radioactive metal. It has a shiny, silvery white color. It has the chemical symbol Th and the atomic number 90. Natural thorium has an atomic weight of 232. Thorium is named after Th ...

                                               

Tin(II) bromide

Tin bromide, also known as stannous bromide, is a chemical compound. Its chemical formula is SnBr 2. It contains tin and bromide ions. The tin is in its +2 oxidation state.

                                               

Tin(II) fluoride

Tin fluoride, also known as stannous fluoride, is a chemical compound. Its chemical formula is SnF 2. It contains tin and fluoride ions. The tin is in its +2 oxidation state.

                                               

Tin(II) sulfide

Tin sulfide, also known as stannous sulfide, is a chemical compound. Its chemical formula is SnS. It contains tin and sulfide ions. The tin is in its +2 oxidation state.

                                               

Tin(IV) chloride

Tin chloride, also known as stannic chloride or tin dioxide, is a chemical compound. Its chemical formula is SnCl 4. It contains tin and chloride ions. The tin is in its +4 oxidation state.

                                               

Tin(IV) fluoride

Tin fluoride, also known as stannic fluoride, is a chemical compound. Its chemical formula is SnF 4. It contains tin and fluoride ions. The tin is in its +4 oxidation state.

                                               

Tin(IV) iodide

Tin iodide, also known as stannic iodide and tin tetraiodide, is a chemical compound. Its chemical formula is SnI 4. It contains tin and iodide ions. The tin is in its +4 oxidation state.

                                               

Tincture of iodine

Tincture of iodine is a disinfectant. It has iodine and potassium iodide dissolved in ethanol and water. Normally, iodine does not dissolve in water. But when potassium iodide is added, the iodine can dissolve. Also, ethanol helps iodine dissolve ...

                                               

Titanium

Titanium is a very strong metal that is used in special applications. The most common isotope has 26 neutrons. Titanium was discovered in 1791 by William Gregor. It is chemical element number 22 on the periodic table. Its symbol is Ti. It has 22 ...

                                               

Toxaphene

Toxaphene is a chemical substance that is very toxic. It is a persistent organic pollutant, and one of the twelve substances listed in the Stockholm Convention on Persistent Organic Pollutants. Its use is banned since 1993. It was used as an inse ...

                                               

Transition metal

The transition metals are a group of metals that are found in the middle of the periodic table. The alkaline earth metals, beginning with beryllium are to the left and the boron group elements are to the right. The term "transition element" was i ...

                                               

Transuranium element

Every transuranium element is a chemical element with an atomic number greater than the atomic number of Uranium. These elements have atomic numbers greater than 92. The word "transuranium" is made of two parts. The Greek prefix trans- means "bey ...

                                               

Tritium

Tritium is an isotope of hydrogen, the lightest element. Tritium has one proton and two neutrons. It heavier than ordinary hydrogen or its isotope deuterium. Hydrogen does not have any neutrons, only a proton. The chemical symbol for Tritium is 3 ...

                                               

Tungsten

Tungsten is a chemical element on the periodic table. It has the chemical symbol W and it has the atomic number 74. It is a steel-gray to white colored metal. In chemistry, it is placed in a group of metal elements named the transition metals. Tu ...

                                               

Unbibium

Unbibium, also known as element 122 or eka-thorium, is the possible chemical element in the periodic table with the placeholder symbol of Ubb and atomic number 122. Unbibium and Ubb are the temporary systematic IUPAC name and symbol, which are us ...

                                               

Unbipentium

Unbipentium is a hypothetical element of the periodic table. It is also known as eka-neptunium. The atomic number of this element is 125. It has the symbol Ubp. The name Unbipentium and the symbol Ubp are temporary IUPAC names. This name and symb ...

                                               

Unbiquadium

Unbiquadium, also known as element 124 or eka-uranium, is the possible chemical element with atomic number 124 and placeholder symbol Ubq. Unbiquadium and Ubq are the temporary IUPAC name and symbol, respectively, until the element is discovered, ...

                                               

Untriseptium

Untriseptium, also called eka-dubnium or element 137, is a possible chemical element which has not been synthesized. Due to instabilities, it is not known if this element is possible, as the instabilities may hint that the periodic table ends soo ...

                                               

Uranium-235

Uranium-235 is a radioactive isotope of uranium. Uranium-235 has 143 neutrons, 92 protons, and an isotope mass of 235.0439299. Uranium-235 has 235 Pa, 235 Np, and 239 Pu as its parent isotopes. As it decays, it produces 231 Th. Uranium-235 has a ...

                                               

Urea

Urea is an organic compound. It was first found in urine in 1773 by the French chemist Jean Rouelle. It is also called Carbamide, and its chemical names are Carbonyl Diamide and Diaminomethanal. In humans, it is a normal component of blood and ma ...

                                               

Valence electron

In chemistry, valence electrons are the electrons in the outside or valence electron shell of an atom. They determine the valency of the atom which is important in how a chemical element reacts with other elements. Elements which have eight valen ...

                                               

Vanadium

Vanadium is chemical element 23 on the periodic table. Its symbol is V. It is named after Vanadis, another name of Freyja. Vanadium is a metal and is part of the group known as the transition metals. It is mostly used in steel where it helps stre ...

                                               

Wax

Wax is an organic chemical substance. It is a type of lipid. Waxes have the following properties: They cannot be dissolved in water Their melting point is above 45 °C They are soft, and easy to shape at room temperature They are hydrophobic, repe ...

                                               

Weak acid

A weak acid is an acid chemical which does not dissociate completely in water solution. This means it does not give all its hydrogen ions into the water. Weak acids typically have a pH between 3 and 6. Acetic acid CH 3 COOH and oxalic acid H 2 C ...

                                               

Xenon

Xenon is a non-metal chemical element. It has the chemical symbol Xe and atomic number 54. It is one of the few elements that are a gas at Standard temperature and pressure. Sir William Ramsay and M. W. Travers discovered this element in 1898. Th ...

                                               

Zinc chloride

Zinc chloride is a chemical compound. It contains zinc and chloride ions. The zinc is in the +2 oxidation state, the only oxidation state zinc has. Its chemical formula is ZnCl 2.

                                               

Adderall

Amphetamine mixed salts is a medication used in the treatment of attention-deficit hyperactivity disorder and narcolepsy. It is sold under the brand name Adderall. The drug contains a mixture of the salts of amphetamine and dextroamphetamine. Bot ...

                                               

Adenoidectomy

Adenoidectomy is the process of taking out a persons adenoids from the back of their throat through the process of surgery. They may be removed for several reasons, including difficulty breathing through the nose and having ear infections. The su ...

                                               

Adjustment disorder

Adjustment disorder happens when a person is unable to cope with or adjust to certain stressors. People who have adjustment disorder often have symptoms such as losing interest, being sad, crying, feeling anxious and constant worries. These sympt ...

                                               

Adrenomyeloneuropathy

Adrenomyeloneuropathy is an inherited disorder. It does not happen very often. It is rare. It is a form of X-linked adrenoleukodystrophy. Leukodystrophy causes a disruption to the myelin covering that protects nerves.

                                               

Alternative medicine

Alternative medicine describes practices used in place of conventional medical treatments. Some patients seek these practices along with conventional medicine. When the patients medical doctor coordinates with an alternative medicine therapist, t ...