Aluminum oxide formula

C.19 Aluminum oxide, alumina, exists in a variety of crystal structures, some of which are beautiful and rare. Write the formula for aluminum oxide, which is a binary compound of aluminum and oxygen. The mass of a rectangular slab of aluminum oxide of dimensions 2.5 cm X 3.0 cm X 4.0 cm is 102 g. What is the density of aluminum oxide ... 

C03-0017. Write correct molecular formulas for aluminum oxide, potassium dichromate, lead(II) nitrate, nitrogen dioxide, sodium sulfate, iodine pentafluoride, manganese(II) acetate, and sodium hypochlorite.. 

As expected, the EDS data set indicates that the polymeric matrix material (the PE-PP blend) is composed only of carbon (hydrogen is not detectable by this method). The particle, however, appears to be composed mainly of aluminum and oxygen along with small amounts of copper. The ratio of aluminum to oxygen is consistent with the chemical formula for aluminum oxide (A1203). The SEM-EDS results are consistent with aluminum oxide and traces of copper as the primary constituents of the particulate contamination. (Al2O3.3H20 is a commonly used fire-retardant additive in polymeric products.)... 

As a result, aluminum oxide with the formula A1203 is formed. 

The total number of electrons lost must equal the total number of electrons gained. The reaction of aluminum with oxygen produces aluminum oxide. The aluminum has three valence electrons to lose. The oxygen has six valence electrons and needs two. The lowest common factor between 3 and 2 is 6. It requires two aluminum atoms, losing three electrons each, to supply six electrons. It will require three oxygen atoms, gaining two electrons each, to account for the six electrons. The resultant compound, aluminum oxide, has the formula A1203. All ions present have an octet of electrons. 

One of the most important electrolytic processes is the extraction of aluminum from an ore called bauxite. This ore is mainly composed of hydrated aluminum oxide, AI2O3 XH2O. (The x in the formula indicates that the number of water molecules per formula unit is variable.) In industry, the scale of production of metals is huge. The electrolytic production of aluminum is over two million tonnes per year in Canada alone. As you know from Faraday s law, the amount of a metal produced by electrolysis is directly proportional to the quantity of electricity used. Therefore, the industrial extraction of aluminum and other metals by electrolysis requires vast quantities of electricity. The availability and cost of electricity greatly influence the location of industrial plants. 

Cr + ions in aluminum oxide (the ruby laser) show a sharp emission (the so-called Ri emission line) at 694.3 nm. To a good approximation, the shape of this emission is Lorentzian, with Av = 330 GHz at room temperature, (a) Provided that the measured peak transition cross section is c = 2.5 x 10 ° cm and the refractive index is = 1.76, use the formula demonstrated in the previous exercise to estimate the radiative lifetime, (b) Since the measured room temperature fluorescence lifetime is 3 ms, determine the quantum efficiency for this laser material. 

This ratio of integers implies that the formula for aluminum oxide is AI2O3. In simple compounds, the metallic elements are written before the nonmetals. 

These calculations are so basic to the field that you should go back and carefully review the two examples in this section the calculation of weight percents in N2O and the inference of the formula for aluminum oxide. Then you can practice stoichiometric calculations on the following pair of problems, which are answered and explained in Appendix A. Many such practice exercises are included in this book so you can determine whether you understand the major concepts of chemistry. It is well worth your time to study these examples and their explanations in Appendix A until you can do the calculations correctly. 

Aluminum reacts with oxygen to yield aluminum oxide. If 5.0 g of A1 reacts with 4.45 g of 02, what is the empirical formula of aluminum oxide ... 

The crisscross method of formula writing makes writing formulas for compounds like aluminum oxide an easier process. In this method, the first step is to write the ionic symbols next to each other. Once this is done, the number of the charge on the cation is written as a subscript for the anion and the number of the charge on the anion is written as a subscript for the cation. 

When writing a chemical formula, you learned that you write the metal element first. Similarly, the metal comes first when naming a chemical compound. For example, sodium chloride is formed from the metal sodium and the non-metal chlorine. Think of other names you have seen in this chapter, such as beryllium chloride, calcium oxide, and aluminum oxide. In each case, the metal is first and the non-metal is second. In other words, the cation is first and the anion is second. This is just one of the rules in chemical nomenclature the system that is used in chemistry for naming compounds. 

Aspirate the Sample Solution prepared for the Aluminum Oxide determination into the photometer, read the percent transmittance in the same manner, and by reference to the standard curve, determine the concentration (C) of sodium, in micrograms per milliliter, in the Sample Solution. Calculate the quantity, in milligrams, of Na20 in the sample taken by the formula... 

Note If the approximate aluminum oxide (AI2O3) content is known, calculate the optimum volume of EDTA solution to be added by the formula... 

Write the formula for each of the following compounds (a) Magnesium sulfide (b) Sodium iodide (c) Lead(IV) oxide (d) Aluminum oxide... 

When a free element reacts with a compound of different elements, the free element will replace one of the elements in the compound if the free element is more reactive than the element it replaces. In general, a free metal will replace the metal in the compound, or a free nonmetal will replace the nonmetal in the compound. A new compound and a new free element are produced. As usual, the formulas of the products are written according to the rules in Chap. 5. The formula of a product does not depend on the formula of the reacting element or compound. For example, consider the reactions of sodium with iron(II) chloride and of fluorine with aluminum oxide ... 

In Chap. 8, the balanced chemical equation was introduced. The equation expresses the ratiota of numbers of formula units of each chemical involved in the reaction. Thus, for the reaction of aluminum w th oxygen to produce aluminum oxide... 

Figure 8.7 The aluminum oxides and hydroxides and their temperatures of interconversion. Hydroxide materials are named along with their chemical formulae oxides all have the composition AI2O3 and so are indicated by the Greek letter associated with the phase. The a-phase is indicated in large font and bold as it is the thermodynamically most stable oxide. Adapted from reference [61].

Oxygen is bivalent in most of its compounds. Since oxygen combines with most of the elements, some of which form several different oxides, the common valences of the elements can be found by considering the formulas of their oxides. Thus sodium, with oxide Na, 0, is univalent calcium (oxide CaO) is bivalent aluminum (oxide ALO ) is tervalent phosphorus (oxides P2O3 and P2O,) is both tervalent and quinquevalent. 

Sodium aluminate (theoretical formula NaA102) has a certain industrial importance not only as an intermediate in the digestion of bauxite in the Bayer process (see Section 3.2.4.2). USA production of sodium aluminate in 1993 was estimated to be 85 10- t/a. Sodium aluminate is produced by dissolving hydrated aluminum oxide in 50% sodium hydroxide. It is utilized in water purification, in the paper industry, for the post-treatment of Ti02-pigments, for the manufacture of aluminum-containing... 

The manufacture of molded articles is usually carried out with mixtures of aluminum oxides with different particle size distributions. This is particularly important when pore-free end-products are required, because this enables a higher volume concentration of aluminum oxide to be obtained than the 74% of ideally cubic close packed spheres by filling the gaps with smaller particles. The particle size distributions used in practice are usually determined using empirically determined approximate formulae (Andreasen or Fuller distribution curves) which take into account the morphology of the individual particles. 

Kaolin is a white clay mostly made up of silicon dioxide, aluminum oxide, iron oxide, titanium dioxide, magnesium oxide and sodium oxide. It was first found in China, in Kao-Ling. European kaolin is formed by the decomposition of feldspath in granite rock in Brittany or Limousin. Kaolin has good absorbent properties and is gentle on the skin it is very well tolerated by very sensitive or reactive skins. It is used for its healing, antiseptic and anti-inflammatory qualities and its excellent coverage in Unna s paste formula. 

Answer Magnesium is Mg. Oxide represents the oxygen ion with a charge of T. or. If you look at this example, only one magnesium ion is needed to balance the charge of one oxide ion. Therefore, the formula is MgO. Sample Determine the formula for aluminum oxide. 

Notice that one of aluminum s three electrons has not been taken up by the oxygen atom. Because all the electrons must be accoimted for, more than one oxygen atom must be involved in the reaction. But, oxygen cannot gain only one electron, so a second aluminum atom must be present to contribute a second electron to oxygen. In all, two Al ions must combine with three ions to form AI2O3. Remember that the charges in the formula for aluminum oxide must add up to zero. 

Write the formulas that correspond to the following names (a) aluminum oxide (used to waterproof fabrics), (b) cobalt(III) fluoride (used to add fluorine atoms to compounds), (c) iron(II) sulfate (in enriched flour), (d) ammonium hydrogen phosphate (coats vegetation to retard forest flres), and (e) potassium bicarbonate (in Are extinguishers). 

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