enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Sodium peroxide - Wikipedia

    en.wikipedia.org/wiki/Sodium_peroxide

    Sodium peroxide is an inorganic compound with the formula Na 2 O 2.This yellowish solid is the product of sodium ignited in excess oxygen. [3] It is a strong base. This metal peroxide exists in several hydrates and peroxyhydrates including Na 2 O 2 ·2H 2 O 2 ·4H 2 O, Na 2 O 2 ·2H 2 O, Na 2 O 2 ·2H 2 O 2, and Na 2 O 2 ·8H 2 O. [4] The octahydrate, which is simple to prepare, is white, in ...

  3. Avogadro constant - Wikipedia

    en.wikipedia.org/wiki/Avogadro_constant

    The Avogadro constant, commonly denoted N A [1] or L, [2] is an SI defining constant with an exact value of 6.022 140 76 × 10 23 mol −1 (reciprocal moles). [3] [4] It is defined as the number of constituent particles (usually molecules, atoms, ions, or ion pairs) per mole and used as a normalization factor in the amount of substance in a sample.

  4. Orders of magnitude (numbers) - Wikipedia

    en.wikipedia.org/wiki/Orders_of_magnitude_(numbers)

    1/52! chance of a specific shuffle Mathematics: The chances of shuffling a standard 52-card deck in any specific order is around 1.24 × 10 −68 (or exactly 1 ⁄ 52!) [4] Computing: The number 1.4 × 10 −45 is approximately equal to the smallest positive non-zero value that can be represented by a single-precision IEEE floating-point value.

  5. Azeotrope tables - Wikipedia

    en.wikipedia.org/wiki/Azeotrope_tables

    This page contains tables of azeotrope data for various binary and ternary mixtures of solvents. The data include the composition of a mixture by weight (in binary azeotropes, when only one fraction is given, it is the fraction of the second component), the boiling point (b.p.) of a component, the boiling point of a mixture, and the specific gravity of the mixture.

  6. Torr - Wikipedia

    en.wikipedia.org/wiki/Torr

    0.019 336 77 psi. The torr (symbol: Torr) is a unit of pressure based on an absolute scale, defined as exactly ⁠ 1 760 ⁠ of a standard atmosphere (101325 Pa). Thus one torr is exactly ⁠ 101325 760 ⁠ pascals (≈ 133.32 Pa). Historically, one torr was intended to be the same as one "millimeter of mercury", but subsequent redefinitions of ...

  7. Protic solvent - Wikipedia

    en.wikipedia.org/wiki/Protic_solvent

    Protic solvent. In chemistry, a protic solvent is a solvent that has a hydrogen atom bound to an oxygen (as in a hydroxyl group −OH), a nitrogen (as in an amine group −NH2 or −NH−), or fluoride (as in hydrogen fluoride). In general terms, any solvent that contains a labile H + is called a protic solvent. The molecules of such solvents ...

  8. Dalton (unit) - Wikipedia

    en.wikipedia.org/wiki/Dalton_(unit)

    The dalton or unified atomic mass unit (symbols: Da or u) is a unit of mass defined as ⁠ 1 12 ⁠ of the mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state and at rest. [1][2] It is a non-SI unit accepted for use with SI. The atomic mass constant, denoted mu, is defined identically, giving mu = ⁠ 1 12 ...

  9. International System of Units - Wikipedia

    en.wikipedia.org/wiki/International_System_of_Units

    The seven SI base units. The SI comprises a coherent system of units of measurement starting with seven base units, which are the second (symbol s, the unit of time), metre (m, length), kilogram (kg, mass), ampere (A, electric current), kelvin (K, thermodynamic temperature), mole (mol, amount of substance), and candela (cd, luminous intensity).