WEBVTT
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we know the rate at which the mass of the
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earth is dissipating is three kilograms per second, and
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it's predicted that it will take 50 billion years for
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that all to decay so we can predict the math
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of the earth mass of the Earth by multiplying the
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rate times the time. We first need to change
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our time into second. So if I have 50
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billion years, that's the same as 50 times 10
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to the nine years. But I know there are
10
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365 days and every year and 24 hours in a
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day and 60 minutes in an hour and 60 seconds
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in a minute. This is equivalent to 1.58 times
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10 to the 18 second. So if it takes
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that much time for all of the earth to dissipate
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by multiplying that by the rate or three kilograms per
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second, we can predict the mass of the earth
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is 4.73 times 10 to the 18 kilograms. Second
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part of the question asked how much of that is
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nitrogen in moles and we know that it's the earth
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is 75.5% nitrogen so we start off with the mass
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of the earth, we can find the mass of
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nitrogen which we can then change two moles. We
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start by taking our initial mass of the earth and
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multiplying by the percentage and that will give us the
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mass of nitrogen and then to go from the massive
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from the massive nitrogen to the moles of nitrogen.
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We need the molar mass of end to and we
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find that using the periodic table one more is equal
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to two times the molar mass of nitrogen where one
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mole is 20 point Oh, won four grands.
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So if the mass of the earth this 4.73 times
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10 to the 18 kilograms times 0.755 This tells us
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the amount of nitrogen in the earth is 3.57 I
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tend to the 18 kilograms. We have to change
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that two grams before we can change it to moles
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. When we do that by multiplying by 1000 or
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3.57 times 10 to the 20 first grams and then
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our next step is to change two moles. Now
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we do this by dividing by the molar mass which
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equals 1.27 times 10 to the 20 moles