Halites

Halite, see Sodium chloride Hausmannite, see Manganese(II,IV) oxide Heavy hydrogen, see HydrogenpH] or name followed by -d... 

The common ores of potassium iaclude (/) sylvinite, a mixture of sylvite, KCl, and halite (2) hartsalz, composed of sylvite, haUte, and kieserite [14567-64-7] MgSO 2 anhydrite 5) camaUitite, camaUite [1318-27-0] KCl. MgCl 6H20, and halite (4) langbeinite ore, langbeinite,... 

K2SO-2 MgSO, and halite and (5) kainite ore, kainite [1318-72-5] 4(KC1 MgSO -11H20, and halite. More than 90% of the estimated potassium reserves occur principally as sylvinite and camaUitite (107). Sylvite, the richest of the minerals at 63% K2O, is the principal economically exploitable reserve. In addition, there are four principal insoluble potassium sUicate minerals, glauconite, leucite, nepheline, and orthoclase—sanidine which range in K2O content from 7 to 22%. These minerals are plentihil but for economic reasons may never be exploited for potassium. 

Other oxoacid salts of the alkali metals are discussed in later chapters, e.g. borates (p. 205), silicates (p. 347), phosphites and phosphates (p. 510), sulfites, hydrogensulfates, thiosulfates, etc. (p. 706) selenites, selenates, tellurites and tellurates (p. 781), hypohalites, halites, halates and perhalates (p. 853), etc. 

ForCb, Bt2 and h, K. c is 4.2 x 10- 7.2 x 10 and 2.0 x 10 mol 1 respectively, thereby favouring the free halogens, whereas Kaik is 7.5 X lO, 2 X lO and 30mol I respectively, indicating a tendency to disproportionation which is overwhelming for CI2 but progressively less pronounced for Br2 and I2. In actuality the situation is somewhat more complicated because of the tendency of the hypohalite ions themselves to disproportionate further to produce the corresponding halite ions ... 

The disulfide is dissolved by aqueous potassium hydroxide, yielding a greenish-yellow solution. At low temperatures no perceptible evolution of gas takes place. Since the disulfide in many respects behaves as a pseudo-halogen, Brown et al. have supposed that the reaction described by Eq. (8) takes place, i.e. a reaction analogous to the formation of halide and halite ions from a halogen and alkali. 

When the solution was acidified the disulfide again separated, but the solution also contained the thiol, and, therefore, these investigators supposed that the reaction had proceeded to form an analog not only of a halite but also of a halate [Eq. (9)]. The existence of the... 

Evaporite deposition is a much more episodic process and thus difficult to quantify. Because seawater is significantly undersaturated with respect to common evaporitic minerals, like gypsum and halite, evaporites are only formed when restricted circulation develops in an ocean basin in which evaporation exceeds precipitation. A geologically recent example is the Mediterranean Sea of 5-6 Myr ago. At this time excess evaporation exceeded the supply of ocean water through shallow inlet(s) from the Atlantic Ocean. As salinity increased, first CaS04, then NaCl precipitated. Over time, salt deposits 2-3 km thick formed. This thickness represents about 40 desiccations of the entire... 

The evaporite source is characterized by covariation of sulfate (from gypsum) and chloride (from halite). That elements can be recycled from the ocean to land by movement of saltbearing aerosols (so-called "cyclic salts") has confused the interpretation of river flux data somewhat. While this cycling generally follows the ratio of salts in the sea, the S/Cl ratio is an exception. Taking the S/Cl ratio of the cyclic component to be 2 (based on compositional data for marine rains) and assuming that all chloride in rivers is cyclic, an upper limit for the cyclic influence can be calculated. 

D and 5 0 data on fluid inclusions and minerals, 8 C of carbonates, salinity of inclusion fluids together with the kind of host rocks indicate that the interaction of meteoric water and evolved seawater with volcanic and sedimentary rocks are important causes for the formation of ore fluids responsible for the base-metal vein-type deposits. High salinity-hydrothermal solution tends to leach hard cations (base metals, Fe, Mn) from the country rocks. Boiling may be also the cause of high salinity of base-metal ore fluids. However, this alone cannot cause very high salinity. Probably the other processes such as ion filtration by clay minerals and dissolution of halite have to be considered, but no detailed studies on these processes have been carried out. 

Naturally occurring salt is known as halite. Halite is what s left when seas evaporate. Michigan, for instance, was underwater several times hundreds of miiiions of years ago. When the seas disappeared, huge deposits of halite were ieft. At one time or another, seas covered aii of the pianet, so halite deposits can be found aimost anywhere. 

The Zag meteorite fell in the western Sahara of Morocco in August 1998. This meteorite was unusual in that it contained small crystals of halite (table salt), which experts believe formed by the evaporation of brine (salt water). It is one of the few indications that liquid water, which is essential for the development of life, may have existed in the early solar system. The halite crystals in the meteorite had a remarkably high abundance of 128Xe, a decay product of a short-lived iodine isotope that has long been absent from the solar system. Scientists believe that the iodine existed when the halite crystals formed. The xenon formed when this iodine decayed. For this reason, the Zag meteorite is believed to be one of the oldest artifacts in the solar system. In this lab, you will use potassium-argon radiochemical dating to estimate the age of the Zag meteorite and the solar system. 

Solution of halite present as bedded or domal Na-Cl salt-evaporite deposits. Na-Ca-Cl... 

Acidifying a solution containing a chlorite gives a solution of HC102. Halite salts are used primarily as bleaching agents. 

At the medium reach, the river flows into the Iberian Depression, with marl and gypsum Miocene deposits in some areas. The dissolution of evaporitic sediments (gypsum, halite, and sodium-sulfates) gives rise to numerous sinkholes. However, subsidence is also being masked by morpho-sedimentary dynamic processes such as aggradation and erosion [12]. 

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