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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
Various oxidized forms of lead are easily reduced to the metal. An example is heating PbO with mild organic reducing agents such as glucose. The mixture of the oxide and the sulfide heated together will also form the metal. [2] 2 PbO + PbS → 3 Pb + SO 2
Although an amphiprotic species must be amphoteric, the converse is not true. For example, a metal oxide such as zinc oxide, ZnO, contains no hydrogen and so cannot donate a proton. Nevertheless, it can act as an acid by reacting with the hydroxide ion, a base: ZnO + 2 OH − + H 2 O → [Zn(OH) 4] 2−. Zinc oxide can also act as a base:
PbO 2 + 2 NaOH + 2 H 2 O → Na 2 [Pb(OH) 6] It also reacts with basic oxides in the melt, yielding orthoplumbates M 4 [PbO 4]. Because of the instability of its Pb 4+ cation, lead dioxide reacts with hot acids, converting to the more stable Pb 2+ state and liberating oxygen: [6] 2 PbO 2 + 2 H 2 SO 4 → 2 PbSO 4 + 2 H 2 O + O 2 2 PbO 2 + 4 HNO ...
But following meals, capillary and arterial blood glucose levels can be significantly higher than venous levels. Although these differences vary widely, one study found that following the consumption of 50 grams of glucose, "the mean capillary blood glucose concentration is higher than the mean venous blood glucose concentration by 35%." [33] [34]
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 .
The cells will use glucose for energy as normal, and any glucose not used for energy will enter the polyol pathway. When blood glucose is normal (about 100 mg/dL or 5.5 mmol/L), this interchange causes no problems, as aldose reductase has a low affinity for glucose at normal concentrations. [citation needed]
Lead(II,IV) oxide is lead(II) orthoplumbate(IV) [Pb 2+] 2 [PbO 4− 4]. [3] It has a tetragonal crystal structure at room temperature, which then transforms to an orthorhombic (Pearson symbol oP28, Space group Pbam, No. 55) form at temperature 170 K (−103 °C). This phase transition only changes the symmetry of the crystal and slightly ...