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The alkaline earth metals (Be, Mg, Ca, Sr, Ba, and Ra) are the second most reactive metals in the periodic table, and, like the Group 1 metals, have increasing reactivity with increasing numbers of energy levels. Beryllium (Be) is the only alkaline earth metal that does not react with water or steam, even if the metal is heated red hot. [9]
Combustion is a chemical reaction that feeds a fire more heat and allows it to continue. Once a fire has started, the resulting exothermic chain reaction sustains the fire and allows it to continue until or unless at least one of the elements of the fire is blocked: foam can be used to deny the fire the oxygen it needs; water can be used to ...
The creation of sparks from metals is based on the pyrophoricity of small metal particles, and pyrophoric alloys are made for this purpose. [2] Practical applications include the sparking mechanisms in lighters and various toys, using ferrocerium; starting fires without matches, using a firesteel; the flintlock mechanism in firearms; and spark testing ferrous metals.
Rhodium is a chemical element; it has symbol Rh and atomic number 45. It is a very rare, silvery-white, hard, corrosion-resistant transition metal. It is a noble metal and a member of the platinum group. It has only one naturally occurring isotope, which is 103 Rh.
A homocycle or homocyclic ring is a ring in which all atoms are of the same chemical element. [1] A heterocycle or heterocyclic ring is a ring containing atoms of at least two different elements, i.e. a non-homocyclic ring. [2] A carbocycle or carbocyclic ring is a homocyclic ring in which all of the atoms are carbon. [3]
A nonane molecule, consisting of nine carbon atoms in a chain with 20 hydrogen atoms surrounding it. In chemistry, catenation is the bonding of atoms of the same element into a series, called a chain. [1] A chain or a ring may be open if its ends are not bonded to each other (an open-chain compound), or closed if they are bonded in a ring (a ...
A cyclic compound or ring compound is a compound in which at least some its atoms are connected to form a ring. [1] Rings vary in size from three to many tens or even hundreds of atoms. Examples of ring compounds readily include cases where: all the atoms are carbon (i.e., are carbocycles),
Chemical reactions such as combustion in fire, fermentation and the reduction of ores to metals were known since antiquity. Initial theories of transformation of materials were developed by Greek philosophers, such as the Four-Element Theory of Empedocles stating that any substance is composed of the four basic elements – fire, water, air and ...