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platinum group with the atomic number 77 , atomic mass 192.2, boiling point at about 44oo degrees celcuis (7952 degrees farinheight), and a melting point of 2450 c (4442 f) the irduims symbol is Ir. Iriduim was discovered by a British chemist by the…

of Matter The fundamental building blocks of matter are atoms and molecules. These make up elements and compounds. An atom is the smallest unit of an element that maintains the properties of that element. And element is a pure substance made of…

Reaction Between Hydrochloric Acid and Sodium Thiosulphate Background Information Reactions can be completed at different rates. The rate of reaction is measured by observing how quickly reactants are used up or how quickly products are forming.…

The only two of greater abundance are oxygen and silicon, thus making aluminum the far most abundant metal on earth. Aluminum has the atomic number thirteen and the chemical symbol Al. It has had many names over the years, including alumina, aluminium…

of reaction Introduction: This investigates how the rate of a chemical reaction depends on the concentration of reactants in the solution. This will be investigated with the following experiment in which dilute hydrochloric acid and sodium…

Attention Deficit Disorder without the Hyperactivity (ADD) is a condition of the brain that makes it difficult for children to control their behavior in school and social settings. This condition is also called by various names: hyperactivity, minimal…

has many meanings. Periodicity is defined as the occurrence of similar properties in elements having similar positions in the periodic table. Periodicity is found through certain periodic trends. There are four periodic trends found in the periodic…

of matter? The four phases of matter include: oSolids oLiquids oGases oPlasmas A phase change involves a change in the physical state of a substance from one phase to another such as: or vice versa oSolid- liquid oLiquid- gas oSolid -…

of chemistry. People have always known that they exist. The Ancient Greeks were the firsts to speculate on the composition of matter. They thought that it was possible that individual particles made up matter. Later, in the Seventeenth Century,…

of the modern atomic theory. In 1750, Rudjer Boscovich, a scientist born in what is now Croatia, suggested the theory that atoms were "uncuttable" might have been wrong. Boscovich thought that atoms contain smaller parts, which in turn contain still…