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Nitrogen is a chemical element; it has symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh in total abundance in the Milky Way and the Solar System.
Nitrogen is a fundamental chemical component of amino acids, the molecular building blocks of protein. As such, nitrogen balance may be used as an index of protein metabolism. [1] When more nitrogen is gained than lost by an individual, they are considered to have a positive nitrogen balance and be in a state of overall protein anabolism.
A science fair or engineering fair is an event hosted by a school that offers students the opportunity to experience the practices of science and engineering for themselves. In the United States, the Next Generation Science Standards makes experiencing the practices of science and engineering one of the three pillars of science education.
Courtesy of Society for Science & the Public. This year's 30 Broadcom MASTERS finalists were announced on Oct. 6. Check out how these pre- and early teens wow-ed the judges with their creativity ...
A science project is an educational activity for students involving experiments or construction of models in one of the science disciplines. Students may present their science project at a science fair, so they may also call it a science fair project. Science projects may be classified into four main types.
A buffer gas usually consists of atomically inert gases such as helium, [1] [2] argon, or nitrogen. [3] Krypton, neon, and xenon are also used, primarily for lighting. [citation needed] In most scenarios, buffer gases are used in conjunction with other molecules for the main purpose of causing collisions with the other co-existing molecules.
A large fraction of the chemical elements that occur naturally on the Earth's surface are essential to the structure and metabolism of living things. Four of these elements (hydrogen, carbon, nitrogen, and oxygen) are essential to every living thing and collectively make up 99% of the mass of protoplasm. [1]
The amount of nitrogen in a chemical substance can be determined by the Kjeldahl method. [21] In particular, nitrogen is an essential component of nucleic acids, amino acids and thus proteins, and the energy-carrying molecule adenosine triphosphate and is thus vital to all life on Earth. [20]