Minerals are naturally occurring substances that are solid and amorphous. They are described by different physical properties such as crystal structure, luster, hardness, color, fracture and more. Metallic minerals are m... More » Science Chemistry

Identify minerals and gems at and; by definition, rocks lack a particular chemical composition or structure and cannot be identified per se. The minerals that compose a rock may be identifi... More » Science Earth Science Geology

Coal is not considered a mineral because it does not have a solid, uniform crystal structure, meaning it doesn't fit the primary definition of a mineral. Coal is primarily made of carbon, but its properties can vary even... More » Science Earth Science Geology
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Arsenic is a naturally occurring semi-metal element. Its atomic number is 33, and its only stable isotope has an atomic weight of 74.92. Arsenic has been used since ancient times, but it was first isolated by the German ... More » Science Chemistry

According to, pCO2 is defined as carbon dioxide concentration. It is further defined as carbon dioxide partial pressure, which is expressed in kilopascals in reference to blood, according to The Free Dictio... More » Science Chemistry

Enthlapy is a thermodynamic property of a system that expresses the ability to perform non-mechanical work and release heat. Enthalpy is represented as H, while specific enthalpy is represented as h. More » Science Chemistry

Cyanaurate, also called aurocyanide, is a chemical reaction that creates a complex anion when the cyanide process is used to dissolve gold. It can also be formed from other metals and radicals. More » Science Chemistry