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The data below tabulates standard electrode potentials (E°), in volts relative to the standard hydrogen electrode (SHE), at: Temperature 298.15 K (25.00 °C; 77.00 °F); Effective concentration (activity) 1 mol/L for each aqueous or amalgamated (mercury-alloyed) species; Unit activity for each solvent and pure solid or liquid species; and
Hydrogen peroxide is a chemical compound with the formula H 2 O 2.In its pure form, it is a very pale blue [5] liquid that is slightly more viscous than water.It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%–6% by weight) in water for consumer use and in higher concentrations for industrial use.
The following table presents pK a values at 20 °C. Values change by about 0.01 per degree of temperature. [1] [3] Good's original 1966 paper had two older buffers (marked with italics) for comparison. In 1972 Good published a second list with three more buffers, and five more were added in 1980.
They are employed in various concentrations in dentistry to effectively bleach teeth. Lower concentrations are common for home use. Compared to hydrogen peroxide, peroxycarboxylic acids are approved as cosmetics in Europe under Regulation (EC) No. 1223/2009 of the European Parliament. [10]
Nitric acid, with a pK value of around −1.7, behaves as a strong acid in aqueous solutions with a pH greater than 1. [23] At lower pH values it behaves as a weak acid. pK a values for strong acids have been estimated by theoretical means. [24] For example, the pK a value of aqueous HCl has been estimated as −9.3.
Dialkyl peroxides, e.g., dicumyl peroxide, are synthesized by addition of hydrogen peroxide to alkenes or by O-alkylation of hydroperoxides. Diacyl peroxides are typically prepared by treating hydrogen peroxide with acid chlorides or acid anhydrides in the presence of base: [1] H 2 O 2 + 2 RCOCl → (RCO 2) 2 + 2 HCl H 2 O 2 + (RCO) 2 O → ...
This hydrogen peroxide then releases hydrogen peroxide: [(HO) 3 B(OOH)] − + H 2 O ⇌ B(OH) − 4 + H 2 O 2. Several metal hydroperoxide complexes have been characterized by X-ray crystallography. Some form by the reaction of metal hydrides with oxygen gas: [17] L n M−H + O 2 → L n M−O−O−H (L n refers to other ligands bound to the ...
Solutions made using hydrogen peroxide at concentrations greater than 50 wt % may cause an explosion. [7] The 1:1 acid–peroxide mixtures will also create an explosion risk even when using common 30 wt. % hydrogen peroxide. [8] Once the mixture has stabilized, it can be further heated to sustain its reactivity. [7]