Base your answers to questions 72 through 75 on the information below.
In the late 19th century, the Hall-Herroult process was invented as an inexpensive way to produce aluminum. In this process, Al2O3(l)
extracted from bauxite is dissolved in Na3AlF6(l) in a graphite-lined tank, as shown in the diagram below. The products are carbon dioxide and molten aluminum metal.
74 Compare the chemical properties of a 300.-kilogram sample of Al2O
3(l) with the chemical properties of a 600.-kilogram sample of Al2O3(l). [1]
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Both samples have the same chemical properties.
75 Write the chemical name for the liquid compound dissolved in the Na3AlF6(l). [1]
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aluminum oxide
NOT Aluminum(III) oxide
76 What is the melting point of the substance that collects at the bottom of the tank? [1]
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933K
77 Compare the density of the Al(l) with the density of the mixture of Al2O3
(l) and Na3AlF6(l). [1]
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The density of the aluminum is greater than the density of the Al2O3
