1. Determine the element's average atomic mass number using the periodic table of the elements. This will be a number with several decimal places behind it. This value is the average
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The atomic mass of an element is the weighted average of the masses of its isotopes. You know that: Antimony121 has a mass of 120.9038 u, x% abundance Antimony123 has a mass of
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If x is the fraction of 63Cu, then (1x) is the fraction of 65Cu. There are two isotopes and their total abundance must be 1. Then 63.55 = 62.93x +1x)64.93 = 62.93x + 64.93  64.93x
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1. Calculate profit. Profit equals revenue minus costs. If revenue is zero, then profit must also equal zero, as profit is always a positive value; a negative profit is, in fact,
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