Analysis of an Alloy

PURPOSE OP EXPERIMENT Determine the percent composition of an aluminum-zinc alloy by measuring the H2 formed upon reaction with acid. 

An alloy is a solution of two or more metals. Amalgams are alloys which involve mercury as one component. A silver amalgam as used in dental work is a solution of silver and mercury. The pewter used to make silverware in Revolutionary War times is an alloy with the composition 85.5% tin, 6.8% copper, 6% bismuth, and 1.7% antimony. Most alloys usually have Physical properties which are different from those of the individual components. In contrast, the chemical properties of the alloy are related to those of the individual components. 

Aluminum-zinc, Al-Zn, alloys react with aqueous solutions of strong acids such as hydrochloric acid, HCl, to produce Al3+(aq), Zn2+(aq), and H2 gas. 

These balanced net ionic equations show that 1 mole of Zn produces 1 mole of 

H2 whereas 1 mole of A1 yields 1.5 mole of H2. Therefore, if an alloy composed of only A1 and Zn reacts completely with HCl, the volume of H2 produced can be used to determine the percent composition of the alloy. The 

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In 1820 del Rio went to the Spanish court to plead for Mexican independence. His paper (1) on the Analysis of an alloy of gold and rhodium from the parting house at Mexico was published in the Annals of Philosophy in October, 1825. The closing years of his long useful life were spent in Mexico, where he died on March 23, 1849. 

CA 24, 3726(1930) to apply to analysis of an alloy in which the metal to be determined is deposited on a Pt electrode without the application of any outside electrical current. Instead, an anode of the baser metal in the aiioy is placed in contact with the solution containing its ions in a compartment separated by a parchment membrane from the solution to be examined... 

ScUi-Sb. Early investigations of the ScNiSb compound showed that it had the MgAgAs-type with a = 0.6062 (Dwight, 1974) from an X-ray powder analysis of an alloy... 

An early investigation of the TbNiSb compound showed that it had the MgAgAs-type with a = 0.6327 (Dwight, 1974), from an X-ray powder analysis of an alloy arc melted under argon and annealed at 973 K. Pecharsky et al. (1983a) and Hartjes and Jeitschko (1995) confirmed the crystal structure and obtained the lattice parameters as a = 0.6302 and a = 0.6304, respectively, by X-ray powder diffraction. For experimental details, see ScNiSb and LaNiSb respectively. 

Analysis of an Alloy of Gold, Rhodium from the Parting House at Mexico... 

From X-ray powder analysis of an alloy obtained by powder metallurgical reaction and annealed at 1173 K, Gd2Co3Ge5 was reported to adopt the Lu2Co3Si5-type structure, a = 0.9683, 5= 1.183, c = 0.5750, yS = 91.65 (Venturini et al. 1986b). 

Early investigations on the TbRu2Ge2 compound determined that it had the CeGa2Al2-type structure with a = 0.4221, c = 0.9879 (Francois et al. 1985) from X-ray powder analysis of an alloy obtained by powder metallurgical reaction at 1273K. The starting components were Tb (3N), Ru (4N) and Ge (4N). 

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