Search results
Results from the WOW.Com Content Network
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.
The following table lists the Van der Waals constants (from the Van der Waals equation) for a number of common gases and volatile liquids. [ 1 ] To convert from L 2 b a r / m o l 2 {\displaystyle \mathrm {L^{2}bar/mol^{2}} } to L 2 k P a / m o l 2 {\displaystyle \mathrm {L^{2}kPa/mol^{2}} } , multiply by 100.
The higher the proton affinity, the stronger the base and the weaker the conjugate acid in the gas phase.The (reportedly) strongest known base is the ortho-diethynylbenzene dianion (E pa = 1843 kJ/mol), [3] followed by the methanide anion (E pa = 1743 kJ/mol) and the hydride ion (E pa = 1675 kJ/mol), [4] making methane the weakest proton acid [5] in the gas phase, followed by dihydrogen.
That value is also the standard formation energy (∆G f °) for an Fe 2+ ion, since e − and Fe(s) both have zero formation energy. Data from different sources may cause table inconsistencies.
Acid strength is the tendency of an acid, symbolised by the chemical formula, to dissociate into a proton, +, and an anion, .The dissociation or ionization of a strong acid in solution is effectively complete, except in its most concentrated solutions.
If X is a gas, instead of [X] the numerical value of the partial pressure in bar is used. [3] If it can be assumed that the quotient of activity coefficients, Γ {\displaystyle \Gamma } , is constant over a range of experimental conditions, such as pH, then an equilibrium constant can be derived as a quotient of concentrations.
Another process uses oxygen to regenerate the nitric acid, using a variety of precursors including glycolic acid and ethylene glycol. [17] As of 2011, this process was only used by Mitsubishi in Japan. [18] A newer method entails oxidative carbonylation of alcohols to give the diesters of oxalic acid: 4 ROH + 4 CO + O 2 → 2 (CO 2 R) 2 + 2 H 2 O
This is a list of gases at standard conditions, which means substances that boil or sublime at or below 25 °C (77 °F) and 1 atm pressure and are reasonably stable. List [ edit ]