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  2. Lead dioxide - Wikipedia

    en.wikipedia.org/wiki/Lead_dioxide

    Whereas the beta form had been identified in 1845, [3] α-PbO 2 was first identified in 1946 and found as a naturally occurring mineral 1988. [ 4 ] The alpha form has orthorhombic symmetry, space group Pbcn (No. 60), Pearson symbol oP 12, lattice constants a = 0.497 nm, b = 0.596 nm, c = 0.544 nm, Z = 4 (four formula units per unit cell). [ 4 ]

  3. Scrutinyite - Wikipedia

    en.wikipedia.org/wiki/Scrutinyite

    Scrutinyite / ˈ s k r uː t ɪ n i. aɪ t / is a rare oxide mineral and is the alpha crystalline form of lead dioxide (α-PbO 2), plattnerite being the other, beta form. The mineral was first reported in 1988 and its name reflects the scrutiny and efforts required to identify it from a very limited amount of available sample material.

  4. List of common physics notations - Wikipedia

    en.wikipedia.org/wiki/List_of_common_physics...

    magnetic flux density also called the magnetic field density or magnetic induction tesla (T), or equivalently, weber per square meter (Wb/m 2) capacitance: farad (F) heat capacity: joule per kelvin (J⋅K −1) constant of integration: varied depending on context speed of light (in vacuum) 299,792,458 meters per second (m/s)

  5. Lead(II) oxide - Wikipedia

    en.wikipedia.org/wiki/Lead(II)_oxide

    3) 2 → 2 PbO + 4 NO 2 + O 2 PbCO 3 → PbO + CO 2. PbO is produced on a large scale as an intermediate product in refining raw lead ores into metallic lead. The usual lead ore is galena (lead(II) sulfide). At a temperature of around 1,000 °C (1,800 °F) in air, the sulfide converted to the oxide: [4] 2 PbS + 2 O 2 → 2 PbO + 2 SO 2

  6. Lead (II,IV) oxide - Wikipedia

    en.wikipedia.org/wiki/Lead(II,IV)_oxide

    3 Pb 2 CO 3 (OH) 2 + O 2 → 2 Pb 3 O 4 + 3 CO 2 + 3 H 2 O. In solution, lead(II,IV) oxide can be prepared by reaction of potassium plumbate with lead(II) acetate, yielding yellow insoluble lead(II,IV) oxide monohydrate Pb 3 O 4 ·H 2 O, which can be turned into the anhydrous form by gentle heating: K 2 PbO 3 + 2 Pb(OCOCH 3) 2 + H 2 O → Pb 3 ...

  7. List of physical quantities - Wikipedia

    en.wikipedia.org/wiki/List_of_physical_quantities

    (Mass) Density (or volume density) ρ: Mass per unit volume kg/m 3: L −3 M: intensive Mean lifetime: τ: Average time for a particle of a substance to decay s T: intensive Molar concentration: C: Amount of substance per unit volume mol⋅m −3: L −3 N: intensive Molar energy: J/mol: Amount of energy present in a system per unit amount of ...

  8. Lead (II) acetate - Wikipedia

    en.wikipedia.org/wiki/Lead(II)_acetate

    Lead(II) acetate is a white crystalline chemical compound with a slightly sweet taste.Its chemical formula is usually expressed as Pb(CH 3 COO) 2 or Pb(OAc) 2, where Ac represents the acetyl group.

  9. Quantization of the electromagnetic field - Wikipedia

    en.wikipedia.org/wiki/Quantization_of_the...

    The energy content of this volume element at 5 km from the station is 2.1 × 10 −10 × 0.109 = 2.3 × 10 −11 J, which amounts to 3.4 × 10 14 photons per (). Since 3.4 × 10 14 > 1, quantum effects do not play a role. The waves emitted by this station are well-described by the classical limit and quantum mechanics is not needed.