ShmoopTube

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And here's your shmoop du jour brought to you by repetition [Man with a paddle hitting a ball]

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repetition repetition...All right some of the info in this drill was part of the

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last drill but don't worry we're not going to repeat ourselves yeah we just [People watching a screen]

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need to be aware that some of the info in this drill was part of the last drill

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but we're not going to repeat ourself... we did deja vu there all

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right moving on okay, the ionization energy for double ionized lithium which

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has the equal three protons is negative 13.6 electron volts which of the

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following is not one of the possible energy levels for double ionized lithium

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and here are the potential answers.... okay if you watch the last video the info on the [A couple watching protons spinning]

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number of protons and ionization energy will sound familiar if you didn't watch

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it well go check it out it's fantastic you'll laugh you'll cry and you'll just [People laughing]

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learn a thing or two maybe and more importantly you'll have the math to

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solve this question well in that last question we use Bohr's formula to find

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the energy level of this atom the formula is e sub N equals Z squared over

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N squared times the ground state energy level looks like that with Z at three [Bohr's equations on a board]

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and a ground state energy level equaling the ionization energy negative thirteen

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point six we know that the energy levels equal 9 over N squared times negative 13

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point 6 well now we can just plug in numbers for n to see what works and what

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doesn't if n equals 1 we find that the energy level equals negative 122.4

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electron volts answer B) is a possible energy level so it's not the right

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answer as we plug in more numbers will find that A) and C) are the n values of 2 [Answers A and C flashing]

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and 5 respectively so those answers are out too but there's no whole number n

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value that'd make D) a possible answer so that's the correct answer for this

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question - N will always be a whole number after all there's no such thing

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as energy level one and a half so it's not too hard to figure out the energy [Girl reading energy level book]

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level as long as we know the atomic number and the ground state energy it

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might take a little trial and error but we'll be able to do the math and get it [Boy stood by a slot machine]

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right.. Sure, it might feel a little repetitive changing out the value for n

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a few times but let's face it repetition is a fact of life in science and math so

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as we were saying and here's your shmoop du jour brought to you by...[Man hitting ball with a paddle]

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