Solubility oxygen in water

Figure 4-462. Oxygen solubility in water at varying temperatures. (From Ref. [189].)...

Interaction between temperature and type of gas (b35) since oxygen solubility in water is temperature dependent. 

Open-circuit decay of potential, 363, 374 Outer Helmholtz plane, 196 Overpotenlial, 101, 106 Oxygen evolution, 172 Oxygen, solubility in water, 155 Oxygen reduction, 175... 

Is oxygen soluble in water Is hydrogen Is air (Consult a text-book regarding the solubility of hydrogen and of oxygen in water.)... 

Properties Fine white powder. Mp (decomposes), d 2.14 (20C), in closed container no detectable loss of available oxygen. Soluble in water, 8% (20C) anhydrous acetic acid 5.6% (20C) insoluble in absolute alcohol (20C). 

White, tetragonal crystals, dj 4.430. mp 230°, dec 270" forming silver chloride and oxygen. Solubility in water (g/100 ml) 10 0D 20 (27 ) 50 (80 ). Slightly sol in ale. Darkens upon exposure to light due to slow decompn. Keep away from tight, organic vapors and oxidizable substances. 

Figure 4.36 Variation of oxygen solubility in water as a function of the temperature for a total constant pressure of P = Pq2 + N2 + Pr20 = 1 bar and for a constant oxygen partial pressure of Pq2 = 1 bar.

Another important example of distribution between phases is that between a gas and the gas species dissolved in water. Gas solubilities are described by Henry s law as discussed for oxygen solubility in water in Chapter 3, Section 3.8.1. 

Oxygen availability is critical for all aerobic fermentations, but oxygen solubility in water is very low (2.18 mmol Ojl" of H2O at 0"C) and drops rapidly with increasing temperature (1.16 and 1.03 mmol O2 at 30 and 40 °C, respectively). The oxygen solubility in water between 0 and 40 C is approximately... 

Tromans D (2000) Modeling oxygen solubility in water and electrolyte solutions. Ind Eng Cheni Res 39 805-815... 

While most terrestrial animals are investigated in batch systems, sometimes supplied with a flow of air, oxygen or gas combinations, the type of applied calorimeter is more important for aquatic animals. In a closed batch system, the oxygen concentration in the water will continuously drop during the experiment. As the oxygen solubility in water is rather small with only 2 to 5 % of the concentration in air, this reduction may occur rapidly. Moreover, excretion of products from the anaerobic metabolism changes the ambient conditions considerably, often in an uncontrolled manner. 

In the standard method, the metal enclosure (called the air chamber) used to hold the hydrocarbon vapors is immersed in water before the test, then drained but not dried. This mode of operation, often designated as the wet bomb" is stipulated for all materials that are exclusively petroleum. But if the fuels contain alcohols or other organic products soluble in water, the apparatus must be dried in order that the vapors are not absorbed by the water on the walls. This technique is called the dry bomb" it results in RVP values higher by about 100 mbar for some oxygenated motor fuels. When examining the numerical results, it is thus important to know the technique employed. In any case, the dry bomb method is preferred. 

Nitrates are prepared by the action of nitric acid on a metal or its oxide, hydroxide or carbonate. All nitrates are soluble in water. On heating, the nitrates of the alkali metals yield only oxygen and the nitrite ... 

Selenium dioxide is a volatile solid obtained when selenium is burnt in air or oxygen. It is very soluble in water, forming a solution of... 

Like all nitrates, it is soluble in water on heating it decomposes evolving nitrogen dioxide and oxygen, but leaving the metal, and not, as is usual with other nitrates, the oxide ... 

Argon is two and one half times as soluble in water as nitrogen, having about the same solubility as oxygen. Argon is colorless and odorless, both as a gas and liquid. Argon is considered to be a very inert gas and is not known to form true chemical compounds, as do krypton, xenon, and radon. 

Tris(2,4-pentanedionato)iron(III) [14024-18-1], Fe(C H202)3 or Fe(acac)3, forms mby red rhombic crystals that melt at 184°C. This high spin complex is obtained by reaction of iron(III) hydroxide and excess ligand. It is only slightly soluble in water, but is soluble in alcohol, acetone, chloroform, or benzene. The stmcture has a near-octahedral arrangement of the six oxygen atoms. Related complexes can be formed with other P-diketones by either direct synthesis or exchange of the diketone into Fe(acac)3. The complex is used as a catalyst in oxidation and polymerization reactions. 

Lead Telluride. Lead teUuride [1314-91 -6] PbTe, forms white cubic crystals, mol wt 334.79, sp gr 8.16, and has a hardness of 3 on the Mohs scale. It is very slightly soluble in water, melts at 917°C, and is prepared by melting lead and tellurium together. Lead teUuride has semiconductive and photoconductive properties. It is used in pyrometry, in heat-sensing instmments such as bolometers and infrared spectroscopes (see Infrared technology AND RAMAN SPECTROSCOPY), and in thermoelectric elements to convert heat directly to electricity (33,34,83). Lead teUuride is also used in catalysts for oxygen reduction in fuel ceUs (qv) (84), as cathodes in primary batteries with lithium anodes (85), in electrical contacts for vacuum switches (86), in lead-ion selective electrodes (87), in tunable lasers (qv) (88), and in thermistors (89). 

Lead nitrate [10099-74-8] Pb(N02)2, mol wt 331.23, sp gr 4.53, forms cubic or monoclinic colorless crystals. Above 205°C, oxygen and nitrogen dioxide are driven off, and basic lead nitrates are formed. Above 470°C, lead nitrate is decomposed to lead monoxide and Pb O. Lead nitrate is highly soluble in water (56.5 g/100 mL at 20°C 127 g/100 mL at 100°C), soluble in alkalies and ammonia, and fairly soluble in alcohol (8.77 g/100 mL of 43% aqueous ethanol at 22°C). Lead nitrate is readily obtained by dissolving metallic lead, lead monoxide, or lead carbonate in dilute nitric acid. Excess acid prevents the formation of basic nitrates, and the desired lead nitrate can be crystallized by evaporation. 

The nitro alcohols generally are soluble in water and in oxygenated solvents, eg, alcohols. The monohydtic nitro alcohols are soluble in aromatic hydrocarbons the diols are only moderately soluble even at 50°C at 50°C the triol is insoluble. 

Alkyl hydroperoxides can be Hquids or soHds. Those having low molecular weight are soluble in water and are explosive in the pure state. As the molecular weight increases, ie, as the active oxygen content is reduced, water solubiUty and the violence of decomposition decrease. Alkyl hydroperoxides are stronger acids than the corresponding alcohols and have acidities similar to those of phenols, Alkyl hydroperoxides can be purified through their alkali metal salts (28). 

Oxo Ion Salts. Salts of 0x0 ions, eg, nitrate, sulfate, perchlorate, hydroxide, iodate, phosphate, and oxalate, are readily obtained from aqueous solution. Thorium nitrate is readily formed by dissolution of thorium hydroxide in nitric acid from which, depending on the pH of solution, crystalline Th(N02)4 5H20 [33088-17 ] or Th(N02)4 4H20 [33088-16-3] can be obtained (23). Thorium nitrate is very soluble in water and in a host of oxygen-containing organic solvents, including alcohols, ethers, esters, and ketones. Hydrated thorium sulfate, Th(S0 2 H20, where n = 9, 8, 6, or 4, is... 

Thioacids have a most disagreeable odour and slowly decompose in air. Their boiling points are lower than those of the coiTcsponding oxygen counterparts and they are less soluble in water, but soluble in most organic solvents. An important dithioacid is dithiocarbonic acid (HO—CS2H). Whilst the free acid is unknown, many derivatives have been prepared such as potassium xanthate giving a yellow precipitate of copper xanthate with copper salts ... 

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