Water, reaction with aluminum

Aluminum alloys are essentially unaffected by dissolved oxygen in pure water up to 350°F (180°C). Although much of aluminum s corrosion resistance is due to the presence of an adherent oxide film, oxygen is not necessary to form the layer. Direct reaction with water can pro-... 

Aluminum is known to undergo another reaction with water, making the hydride ... 

Aluminum alkyls undergo many reactions that are typical of covalent metal compounds. Compounds containing methyl, ethyl, and propyl groups ignite spontaneously in air. The reactions with water take place with explosive violence when the alkyl groups contain four or fewer carbon atoms. 

Figure 3 Examples of compounds formed from the reaction of aluminum alkyls with water.

Read the label of the crystal drain cleaner package. Understand that the compound is solid sodium hydroxide that contains aluminum. When the material is added to water, sodium hydroxide dissolves rapidly, producing heat. Aluminum reacts with water in the basic solution to produce Al(OH)4 ions and hydrogen gas. Is aluminum oxidized or reduced in the reaction Is hydrogen oxidized or reduced in the reaction Explain your answers. 

Reaction of the products of reduction with lithium aluminum hydride with water is very exothermic. This is especially true of reductions in which an excess of lithium aluminum hydride has been used. In such cases it is advisable to decompose the unreacted hydride by addition of ethyl acetate (provided its reduction product - ethanol - does not interfere with the isolation of the products). Then normal decomposition with water is carried out followed by acids [5i] or bases [121]. 

First, determine the chemical formula of aluminum ethoxide, and then write a balanced equation for the reaction of aluminum ethoxide with water. 

The waterborne basecoat consists of a urethane or an acrylic dispersion with passivated aluminum for metallic glamour. The aluminum must be passivated to prevent reaction with water and the evolution of hydrogen gas. Passivating agents can include polymers, hexavalent chromium (now mandated for removal), or phosphate esters. The basecoat is pre-baked (with infrared or thermal ovens) to release the majority of the water prior to clear-coat application. 

The reactions of aluminum alkyls with water take place explosively when the alkyl group is C4H9 or smaller. In reactions of this type, the alkyl behaves as if it contained R that abstracts protons from polar bonds to hydrogen as shown in the following equation ... 

Both gallium hydride complexes are obtained as white, crystalline powders which remain white when stored at room temperature in the absence of air and moisture for periods in excess of one year. Their reaction with water is moderate when compared to the analogous aluminum hydride complexes. They undergo typical reactions for an [MH4] species, e.g.,... 

If excess oxalyl chloride (and/or phosgene) is not removed, the vigorous reaction with water during decomposition of the aluminum chloride complex contributes to hydrolysis of the product acid chloride by increasing the time needed to complete this step. The more dilute solution achieved by additional solvent helps to prevent this hydrolysis as does maintenance of a low temperature during decomposition of the complex. 

The linear CO stretching frequency for the carbonylated platinum colloid while lower than that found for surface bound CO, is in the range reported for the platinum carbonyl clusters [Pt 3 (CO) 6 ] n / sind we find that the carbonylated colloid is easily transformed into the molecular cluster [Pt 12 (CO) 24 ] (10) reaction with water. The cluster was isolated in 50 yield based on platinum content of the precipitate by extraction with tetraethylammonium bromide in methanol from the aluminum hydroxide precipitated when water is added to the aluminoxane solution. The isolation of the platinum carbonyl cluster reveals nothing about the size or structure of the colloidal platinum particles, but merely emphasizes the high reactivity of metals in this highly dispersed state. The cluster isolated is presumably more a reflection of the stability of the [Pt3(CO)6]n family of clusters than a clue to the nuclearity of the colloidal metal particles - in a similar series of experiments with colloidal cobalt with a mean particle size of 20A carbonylation results in the direct formation of Co2(CO)8. 

ACGIH TLV TWA 2 mg(Al)/m3 DOT CLASSIFICATION 8 Label Corrosive SAFETY PROFILE Moderately toxic by ingestion. Experimental teratogenic and reproductive effects. Mutation data reported. The dust is an irritant by ingestion, inhalation, and skin contact. Highly exothermic polymerization reactions with alkenes. Incompatible with nitrobenzenes or nitrobenzene + phenol. Highly exothermic reaction with water or steam produces toxic ftimes of HCl. See also ALUMINUM COMPOUNDS, CHLORIDES, and HYDROCHLORIC ACID. 

The Raney nickel alloy will react with water at 70°-85°C to give the skeletal nickel in the presence of aluminum hydroxide. The resulting catalyst is active after washing with alcohol . Since no base is present, the extensive water washings are not required. The reaction with water can be promoted by the addition of a small amount of base, and, further, some Bayerite, Al(OH)3, to further facilitate the aluminum removal. ... 

The drain cleaner Drano consists of aluminum turnings mixed with sodium hydroxide. When it is added to water, the sodium hydroxide dissolves and releases heat. The aluminum reacts with water to generate bubbles of hydrogen and aqueous ions. Write a balanced net ionic equation for this reaction. 

As discussed previously, once exposed to water, even high ambient humidity, aluminum phosphide will generate phosphine gas. Therefore, atmospheric dissipation is expected to be the primary fate process for phosphine. In addition to phosphine being generated from the reaction of aluminum phosphide with water, the other reaction product is aluminum hydroxide, a common constituent of clay. If the liberated phosphine (PH3) burns it will produce phosphorus pentoxide (P2O5), which when exposed to water will form orthophosphoric acid (H3PO4). 

Derivation Reaction of aluminum arsenide with water or hydrochloric acid, electrochemical reduction of arsenic compounds in acid solutions. 

In alkaline solution it is more appropriate to use OH- rather than IT1" (see Topic E2). The other species present may also be different from those in acid, as many metal cations form insoluble hydroxides or even oxoanions (see Topic E4). As an example, consider the reaction of aluminum metal with water to form [Alm(OH)4]- and H2. The balanced half reactions are... 

Describe how the weak monoprotic acid hydrofluoric acid, HF (used in aluminum processing) acts when it is added to water, including a description of the nature of the particles in solution before and after the reaction with water. 

Normalization is based on the average value of oxygen Auger (510 eV) signals from specimens exposed to water vapor for 6.65 x 10 to 1.33 Pa-s. Comparable results were obtained from the companion XPS studies. The results show that the initial rate of reaction of clean aluminum surfaces with water vapor is rapid and reaches saturation after about 2.7 x 10 Pa-s exposure that is, the extent of reaction with aluminum is limited. XPS results indicate that the reactions are associated with the formation of an oxide or a hydrated oxide layer. The limited reactions with water vapor are consistent with previous results on a high-strength AISI 4340 steel [4], The rate of reaction, however, is 10 to 10 times faster than the corresponding rate (associated with the slow, second step) of reaction with AISI 4340 steel. 

CHLOROBIS (2-METHYLPROPYL)-ALUMINUM ( 1 7 7 9 - 2 5 - 5 ) [(CH3)2CHCH2]2A1C1 Pyrophoric ignites spontaneously in air (flashpoint 0°F/-18°C). Reacts with air, forming hydrogen chloride and aluminum oxide fumes. Violent, explosive reaction with water. Reacts with steam, acids, alcohols, amines, ammonium persulfate, bromine dioxide, carbon dioxide. 

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