Unformatted text preview: The number of atoms in 10.0 g (0.371 mol) of aluminum is 6.022 X 10 23 atoms 0.371 melPd X 1 melPd = 2.23 X 10 23 atoms Reality Check: One mole of Al has a mass of 26.98 g and contains 6.022 X 1023atoms. Our sample is 10.0 g, which is roughly 1/3 of 26.98. Thus the calculated amount should be on the order of 1/3 of 6 X 10 23 ,which it is. SEE EXERCISE 3.42 A silicon chip used in an integrated circuit of a microcomputer has a mass of 5.68 mg. How many silicon (Si) atoms are present in the chip? Solution The strategy for doing this problem is to convert from milligrams of silicon to grams of silicon, then to moles of silicon, and finally to atoms of silicon: 1 Si 5.68 mgst X g = 5.68 X 103 g Si 1000 mgst 1 mol Si 5.68 X 103 g8t X = 2.02 X 104 mol Si 28.09 g8t 6.022 X 10 23 atoms 104 mel8t X = 1.22 X 10 20 atoms 1 mel8t 2.02 X...
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 Spring '10
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 Organic chemistry, Atom, Mole, Aluminium, International System of Units, Kilogram, Avogadro constant

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