QRNeditor: Added diagram of periodic table

2021-06-20T19:28:37Z

Added diagram of periodic table

QRNeditor: Formatting edits

2021-05-08T12:22:33Z

Formatting edits

Admin: Created page with "Elements Dobereiner's Triads are groups of three elements having similar properties. They are named after the German chemist Johann Dobereiner. He observed that when three el..."

2021-04-18T21:55:11Z

Created page with "Elements Dobereiner's Triads are groups of three elements having similar properties. They are named after the German chemist Johann Dobereiner. He observed that when three el..."

Show changes

← Older revision		Revision as of 19:28, 20 June 2021
Line 2:		Line 2:

	=== Periodic table ===		=== Periodic table ===
		+	[[File:1024px-Periodic Table Chart.png\|none\|thumb\|800x800px]]
	Dobereiner's Triads are groups of three elements having similar properties. They are named after the German chemist Johann Dobereiner. He observed that when three elements of any particular triad were arranged in order of their increasing atomic masses, the atomic mass of the middle element was roughly the mean or average of the atomic masses of the other two elements. He was the first to classify elements into groups based on John Dalton's assertions		Dobereiner's Triads are groups of three elements having similar properties. They are named after the German chemist Johann Dobereiner. He observed that when three elements of any particular triad were arranged in order of their increasing atomic masses, the atomic mass of the middle element was roughly the mean or average of the atomic masses of the other two elements. He was the first to classify elements into groups based on John Dalton's assertions

@@ Line 1: / Line 1: @@
-Elements
+== Chemical elements ==
 Dobereiner's Triads are groups of three elements having similar properties. They are named after the German chemist Johann Dobereiner. He observed that when three elements of any particular triad were arranged in order of their increasing atomic masses, the atomic mass of the middle element was roughly the mean or average of the atomic masses of the other two elements. He was the first to classify elements into groups based on John Dalton's assertions
@@ Line 41: / Line 42: @@
 Isotopes – any of the several different forms of an element each having different atomic mass (mass number). Isotopes of an element have nuclei with the same number of protons (the same atomic number) but different numbers of neutrons. Therefore, isotopes have different mass numbers, which give the total number of nucleons – the number of protons plus neutrons
 Group – also known as a family, is a vertical column in the periodic table of the elements. Elements in a group have the same number of electrons in their outermost shell
@@ Line 143: / Line 145: @@
 Of the 88 natural elements, only 20 are found in the native state
 '''Hydrogen''' (H), atomic number 1 – from Greek for ‘water generator’
@@ Line 765: / Line 768: @@
 '''Copernicium''' (Cn), atomic number 112 – named after Nicolaus Copernicus. Accepted as a permanent name in 2010. Previously the element was known under the temporary IUPAC systematic element name Ununbium (Uub). Copernicium is made from fusing of zinc and lead. Copernicium has been observed as decay products of flerovium
-'''Ununtrium''' (Uut), atomic number 113
+'''Nihonium''' (Nh), atomic number 113 – named after one of the two Japanese pronunciations for the name of Japan. It is the first element to be named after a location in East Asia. Previously the element was known under the temporary IUPAC systematic element name Ununtrium (Uut)
 '''Flerovium''' (Fl), atomic number 114 – named after Russian physicist Georgy Flyorov, the founder of the Joint Institute for Nuclear Research in Dubna, Russia, where the element was discovered. Accepted as a permanent name in 2012. Previously the element was known under the temporary IUPAC systematic element name Ununquadium (Uuq)
-'''Ununpentium''' (Uup), atomic number 115
+'''Moscovium''' (Mc), atomic number 115 – named after the Moscow Oblast which is the location of the Joint Institute for Nuclear Research. Previously the element was known under the temporary IUPAC systematic element name Ununpentium (Uup)
 '''Livermorium''' (Lv), atomic number 116 – named after the Lawrence Livermore National Laboratory, which was involved in its discovery in 2000. Accepted as a permanent name in 2012. Previously the element was known under the temporary IUPAC systematic element name Ununhexium (Uuh)
-'''Ununseptium''' (Uus), atomic number 117 – synthesized in 2010
+'''Tennessine''' (Ts), atomic number 117 – named after the state of Tennessee which is home to Oak Ridge National Laboratory. Synthesized in 2010. Previously the element was known under the temporary IUPAC systematic element name Ununseptium (Uus)
-'''Ununoctium''' (Uuo), atomic number 118 – the temporary IUPAC name for the superheavy element, currently the highest atomic number assigned to a reputedly discovered element
+'''Oganesson''' (Og), atomic number 118 – named after the Russian nuclear physicist Yuri Oganessian who led the team that synthesized it. Previously the element was known under the temporary IUPAC systematic element name Ununoctium (Uuo)
 Ununennium, also known as eka-francium or element 119, is the temporary name of a chemical element that has the temporary symbol Uue. To date, attempted syntheses of this element have been unsuccessful
@@ Line 781: / Line 784: @@
 Unbihexium – an undiscovered superheavy chemical element with temporary symbol Ubh and atomic number 126. The element is predicted to be near the centre of the hypothesized island of stability, and thus may have a very long half-life
+== Acids ==
 '''Acid''' – any chemical compound that, when dissolved in water, gives a solution with a hydrogen ion activity greater than in pure water, i.e. a pH less than 7.0
@@ Line 840: / Line 841: @@
 When a metal is added to an acid, hydrogen gas is one of the reaction products
+== Salts ==
 '''Salt''' – a solid compound formed from the combination of an acid and a base by the replacement of hydrogen ions in the acid by positive ions in the base
@@ Line 879: / Line 878: @@
 Potassium bromide – KBr. Widely used as an anticonvulsant and a sedative in the late 19th and early 20th centuries
+== Hydrocarbons ==
 '''Hydrocarbon''' – an organic compound consisting entirely of hydrogen and carbon
@@ Line 914: / Line 911: @@
 Naphthalene – a white crystalline strong-smelling hydrocarbon made from coal tar or petroleum and used in organic synthesis and as a fumigant in mothballs
+== Compounds ==
 Empirical formula of a chemical compound is the simplest positive integer ratio of atoms present in a compound. A simple example of this concept is that the empirical formula of hydrogen peroxide, or H<sub>2</sub>O<sub>2</sub>, would simply be HO
@@ Line 1,029: / Line 1,024: @@
 Guy-Lussac and Humboldt discovered that water is formed by two parts of hydrogen and one part of oxygen in 1805. Acidic water has more H<sup>+</sup> ions (protons), less OH<sup>-</sup> ions
-Water can disassociate to form equal numbers of positively-charged hydrogen ions (H+) and negatively-charged  hydroxyl ions (OH-). Substances that disturb this balance when added to water are called acids and alkalis
+Water can disassociate to form equal numbers of positively charged hydrogen ions (H+) and negatively charged hydroxyl ions (OH-). Substances that disturb this balance when added to water are called acids and alkalis
 '''Alloy''' – a mixture of metals, or a mixture of a metal with a non-metal in which the metal is the major component
@@ Line 1,090: / Line 1,083: @@
 Cupronickel is used in many silver-coloured modern circulation coins
+== Polymers ==
 '''Polymer''' – a large molecule made up of chains or rings of linked monomer units
@@ Line 1,119: / Line 1,110: @@
 Acetate – a type of rayon
+== Crystallography ==
 Crystal – a solid material, whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions
@@ Line 1,142: / Line 1,131: @@
 X-ray crystallography – the distance between adjacent planes in the regular matrix within crystals is similar to the X-ray wavelength so X-rays can discern the relative position of things within crystals
+== Processes ==
 Bayer process – refines bauxite to produce alumina (aluminium oxide). The aluminium oxide must be purified before it can be refined to aluminium metal
@@ Line 1,167: / Line 1,154: @@
 Wacker process or the Hoechst-Wacker process originally referred to the oxidation of ethylene to acetaldehyde by oxygen in water in the presence of a palladium tetrachloride catalyst. The same basic reaction is currently used to produce aldehydes and ketones from a number of alkenes with the Monsanto process for producing acetic acid
+== Glossary ==
 Absorption – the incorporation of a substance in one state into another of a different state (e.g., liquids being absorbed by a solid or gases being absorbed by a liquid)

Physical World/Chemistry - Revision history

QRNeditor: Added diagram of periodic table

QRNeditor: Formatting edits

Admin: Created page with "Elements Dobereiner's Triads are groups of three elements having similar properties. They are named after the German chemist Johann Dobereiner. He observed that when three el..."