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Aluminium carbonate (Al 2 (CO 3) 3), is a carbonate of aluminium.It is not well characterized; one authority says that simple carbonates of aluminium are not known. [2] However related compounds are known, such as the basic sodium aluminium carbonate mineral dawsonite (NaAlCO 3 (OH) 2) and hydrated basic aluminium carbonate minerals scarbroite (Al 5 (CO 3)(OH) 13 •5(H 2 O)) and ...
In the Earth's crust, aluminium is the most abundant metallic element (8.23% by mass [33]) and the third most abundant of all elements (after oxygen and silicon). [65] A large number of silicates in the Earth's crust contain aluminium. [66] In contrast, the Earth's mantle is only 2.38% aluminium by mass. [67]
720p (720 lines progressive) is a progressive HD signal format with 720 horizontal lines/1280 columns and an aspect ratio (AR) of 16:9, normally known as widescreen HD (1.78:1). All major HD broadcasting standards (such as SMPTE 292M ) include a 720p format, which has a resolution of 1280×720.
Aluminium oxide (or aluminium(III) oxide) is a chemical compound of aluminium and oxygen with the chemical formula Al 2 O 3. It is the most commonly occurring of several aluminium oxides, and specifically identified as aluminium oxide. It is commonly called alumina and may also be called aloxide, aloxite, or alundum in various forms and ...
A variety of compounds of empirical formula AlR 3 and AlR 1.5 Cl 1.5 exist. [22] The aluminium trialkyls and triaryls are reactive, volatile, and colorless liquids or low-melting solids. They catch fire spontaneously in air and react with water, thus necessitating precautions when handling them.
Aluminium was used heavily in aircraft production and was a strategic material of extreme importance; so much so that when Alcoa (successor of Hall's Pittsburgh Reduction Company and the aluminium production monopolist in the United States at the time) did not expand its production, the United States Secretary of the Interior proclaimed in 1941 ...
A metamorphic rock called emery that is mostly made of corundum which is an aluminum oxide. This is an example of an aluminum deposit. Aluminum is the third most abundant element in the lithosphere at 82,000 ppm. It occurs in low levels, 0.9 ppm, in humans. [1] Aluminum is known to be an ecotoxicant and expected to be a health risk to people.
The Earth formed from the same cloud of matter that formed the Sun, but the planets acquired different compositions during the formation and evolution of the Solar System. In turn, the natural history of the Earth caused parts of this planet to have differing concentrations of the elements. The mass of the Earth is approximately 5.98 × 10 24 kg.