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  1. Ethylenediaminetetraacetic acid ( EDTA ), also called EDTA acid after its own abbreviation, is an aminopolycarboxylic acid with the formula [CH 2 N (CH 2 CO 2 H) 2] 2. This white, water-insoluble solid is widely used to bind to iron (Fe 2+ /Fe 3+) and calcium ions (Ca 2+ ), forming water-soluble complexes even at neutral pH.

    • C₁₀H₁₆N₂O₈
    • 200-449-4
    • 0.860 g cm−3 (at 20 °C)
    • 292.244 g·mol−1
  2. Viviparus georgianus, commonly known as the banded mystery snail, is a species of large freshwater snail in the family Viviparidae, the river snails. It is native to North America, generally found from the northeastern United States to Florida and the Gulf of Mexico, and thrives in eutrophic lentic environments such as lakes, ponds and some low ...

  3. Sodium chloride / ˌsoʊdiəm ˈklɔːraɪd /, [8] commonly known as edible salt, is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chlorine ions. It is transparent or translucent, brittle, hygroscopic, and occurs as the mineral halite. In its edible form, it is commonly used as a condiment and food ...

  4. Calcium carbonate is the active ingredient in agricultural lime and is produced when calcium ions in hard water react with carbonate ions to form limescale. It has medical use as a calcium supplement or as an antacid, but excessive consumption can be hazardous and cause hypercalcemia and digestive issues.

  5. bar: 10 −5 bar. barye (CGS unit) 10 Ba. The pascal (symbol: Pa) is the unit of pressure in the International System of Units (SI). It is also used to quantify internal pressure, stress, Young's modulus, and ultimate tensile strength. The unit, named after Blaise Pascal, is an SI coherent derived unit defined as one newton per square metre (N ...

  6. Fibonacci sequence. A tiling with squares whose side lengths are successive Fibonacci numbers: 1, 1, 2, 3, 5, 8, 13 and 21. In mathematics, the Fibonacci sequence is a sequence in which each number is the sum of the two preceding ones. Numbers that are part of the Fibonacci sequence are known as Fibonacci numbers, commonly denoted Fn .

  7. Viète. de Moivre. Euler. Fourier. v. t. e. In trigonometry, trigonometric identities are equalities that involve trigonometric functions and are true for every value of the occurring variables for which both sides of the equality are defined. Geometrically, these are identities involving certain functions of one or more angles.