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Piperonyl butoxide (PBO) is a pale yellow to light brown liquid [1] organic compound used as an adjuvant component of pesticide formulations for synergy.That is, despite having no pesticidal activity of its own, it enhances the potency of certain pesticides such as carbamates, pyrethrins, pyrethroids, and rotenone. [2]
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) the sulfide is converted to the oxide: [5] 2 PbS + 3 O 2 → 2 PbO + 2 SO 2
Lead sesquioxide, Pb 2 O 3, which is a lead (II,IV) oxide as well (lead(II) metaplumbate(IV) [Pb 2+][PbO 2− 3]), reddish yellow Pb 12 O 19 , monoclinic, dark-brown or black crystals The so-called black lead oxide , which is a mixture of PbO and fine-powdered Pb metal and used in the production of lead–acid batteries .
Lead(II) sulfate is poorly soluble, as can be seen in the following diagram showing addition of SO 2− 4 to a solution containing 0.1 M of Pb 2+. The pH of the solution is 4.5, as above that, Pb 2+ concentration can never reach 0.1 M due to the formation of Pb(OH) 2. Observe that Pb 2+ solubility drops 10,000 fold as SO 2− 4 reaches 0.1 M.
Lead(II,IV) oxide is prepared by calcination of lead(II) oxide (PbO; also called litharge) in air at about 450–480 °C: [5] 6 PbO + O 2 → 2 Pb 3 O 4. The resulting material is contaminated with PbO. If a pure compound is desired, PbO can be removed by a potassium hydroxide solution: PbO + KOH + H 2 O → K[Pb(OH) 3]
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[1] [2] [3] Figure 1 is a schematic representation of the three main growth modes for various surface coverages. Determining the mechanism by which a thin film grows requires consideration of the chemical potentials of the first few deposited layers. [2] [7] A model for the layer chemical potential per atom has been proposed by Markov as: [7]
The California DMV apologized for a license plate appearing to mock the Oct. 7 attacks on Israel. The car owner's son said it was being misinterpreted.