WEBVTT
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to begin this question with better mind. What is
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the number off atoms of gold that are in 12
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kilograms off gold? For that, we have to
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use a gratis constant that tells us that in one
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mole off good, there are 6.2 times 10 to
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23 gold atoms, so it gives us follows in
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one mood. We have 6.2 times stand to 23
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atoms before we now have to discover how many rolls
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off. Good are 12 kilograms. For that,
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we have to use these information. These information tells
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us the following. It tells us that one more
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off gold has 197 grounds. Sure. Now we
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can do the following one Mode has 197 grounds.
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Let me converts to kill a rooms by multiplying by
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10 to the minus three and now acts. Moons
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are present in 12 kilograms of gold. Then doing
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the cross multiplication, we got that 0.197 times X
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is equals to 12 so acts is equals to 12
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divided by 0.197 and this is the number off moles
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off gold in 12 kilograms off gold. Now we
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would have this result and use here because now we
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have 12 divided by 0.197 balls off goat and that
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number off newly off good has why atoms again do
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the cross multiplication. To get that why it's equals
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to 12 divided by 0.1 97 times 6.2 times.
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Stand to 23. Now to calculate the charge in
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all electrons, we have to do one thing,
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which is the following notice that each goat atom has
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79 electrons. Therefore, we can say that one
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at all has 79 electrons, then 12 divided by
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0.197 times 6.0 truth time. Stand to 23 atoms
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has w electrons do the cross multiplication and then the
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number off electrons is equals to 12 divided by 0.1
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and seven times 6.0 Truth I understand to 23 times
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79 and this is the number off electrons. And
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finally remember that the charge off each electron is Stephen
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by minus 1.602 times stand toe minus 90 problems before
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finishing the question. Let me organize the board.
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Okay, so this is the number off electrons in
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12 kilograms of good. Now to discover one is
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the net charge off those electrons Onley. All we
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have to do is multiply the number off electrons by
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the charge off each Elektrim and then the charge off
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all electrons is equals to minus 1.60 Choose time.
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Stand to my house. 19 times 12 divided by
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0.19756 points is your true time, Stan 23 times
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79. And these results in a charge off approximately
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minus 4.6 times. Stand to the eight problems.
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This is the charge off all electrons contained in 12
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kilograms off gold. For the second question, it
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asks us what is the next charge off news?
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12 kilograms of gold. This is a very easy
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question because a gold atom has zero. That charge
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because it has 79 electrons and 79 pro tools there
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for the nets charge often atom zero, which means
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that the net charge off 12 kilograms off bathrooms.
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It's outside zero. Therefore, zero is the answer
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for the second item