An alloy is a mixture of two elements, A mixture contains two or more different substances that are not joined together.
Alloys. An alloy is a mixture of two elements, one of which is a metal. Alloys often have properties that are different to the metals they contain. This makes them more useful than the pure metals alone. For example, alloys are often harder than the metal they contain.  An alloy is a mixture of metals or a mixture of a metal and another element. Alloys are defined by metallic bonding character. An alloy may be a solid solution of metal elements (a single phase) or a mixture of metallic phases (two or more solutions). Intermetallic compounds are alloys with a defined stoichiometry and crystal structure Mixtures of metals, called alloys, are more commonly used than the pure metal. By alloying, some of the important properties of metals can be improved. 1  Solder, which is used in the electronics industry, is a mixture of tin and lead. 1 Solder, which is used in the electronics industry, is a mixture of tin and lead. 2  One type of solder (63% tin and 37% lead) has a lower melting point but is harder than either of the metals. 3  These properties allow it to be used successfully. 4  An amalgam is an alloy based on mercury. 1 Alloys-mixtures in which the main elememt (or elements) are metal(s). 2  A more technical definition of an alloy is a partial or complete solid solution of one or more elements in a metallic matrix. 3  Common examples of alloys include bronze, brass and steels. These include: 1  Homogeneous Mixtures-in which the two or more substances that form the mixture are evenly distributed throughout the mixture, e.g. vinegar is a homogeneous mixture of ethanoic acid and water. Homogeneous means that there is only one phase present-ie the whole material is solid (or liquid, or gas). Mixture means that each metal can be present in any proportion. If an alloy was a compound, you could only get one ratio of metals present, whereas in reality you can go from 0% to 100% of each metal in an alloy.  An element contains just one type of atom. A compound contains two or more types of atom joined together. A mixture contains two or more different substances that are not joined together. The different substances in a mixture can be elements or compounds.  You might see the word alloy described as a mixture of metals, but that's a little bit misleading because some alloys contain only one metal and it's mixed in with other substances that are nonmetals (cast iron, for example, is an alloy made of just one metal, iron, mixed with one nonmetal, carbon).  For instance water is always two atoms of hydrogen to 1 atom of oxygen. A mixture does not have a specific ratio of the substances which make it up. Alloys can be in any proportion, and are therefore, mixtures, despite the fact that in a metal alloy the metal atoms are covalently bonded by pi bonds. Update: pisgahchemist: Alloys can be in any proportion, and are therefore, mixtures. But think of the different crystalline phases of brass, which only exist over different and distinct ranges of Cu:Zn ratios, with heterogeneous mixtures in between (see Cu:Zn phase diagram). 1 Colloids are very important in biology and medicine. 2  Alloys-mixtures in which the main elememt (or elements) are metal(s). 3  A more technical definition of an alloy is a partial or complete solid solution of one or more elements in a metallic matrix. These include: 1  Homogeneous Mixtures-in which the two or more substances that form the mixture are evenly distributed throughout the mixture, e.g. vinegar is a homogeneous mixture of ethanoic acid and water. An alloy is a homogeneous mixture of two or more elements, at least one of which is a metal, where the resulting material has metallic properties. For example steel is an alloy made up mainly from iron with a small amount of carbon (to make it harder), manganese (to make it strong) and chromium (to prevent rusting). In a mixture, the substances that make up the mixture: are not in a fixed ratio. Imagine, for example, that you have 250 ml of water and you add sand to the water. It doesn't matter whether you add 20 g, 40 g, 100 g or any other mass of sand to the water; it will still be called a mixture of sand and water.
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why are alloys classified as mixtures