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HANSOL: Hey!

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Time for lab.

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PHIL: This is probably the
hardest experiment, so--

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[MUSIC PLAYING]

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[MUSIC PLAYING]

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NARRATOR: So far in 5.301, the
students have learned many of

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the techniques that organic
chemists use every day.

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Today they'll learn column
chromatography.

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It's the last technique before
their original research

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project next week.

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They are growing more
comfortable in the lab, but

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Phil puts their new-found
confidence in perspective.

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PHIL: On an average
day in my life,

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I'll set up two reactions.

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I'll do two extractions
and run two columns.

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So when you think about all the
things that you've done

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over the past two weeks, the
goal is, essentially, to be

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able to do all of
that in one day.

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5.301 CLASS: One,
two,three, chem!

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[MUSIC PLAYING]

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NARRATOR: And so it begins.

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But packing and running
a column is not easy.

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PHIL: Yeah, ideally for this
experiment, you would have one

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mentor mentoring each student.

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TENGFEI: I'm so nervous
for them.

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DAN: Feifei made me
feel like this lab

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is much more difficult.

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IKE: Hopefully, it's not as bad
as they say it will be.

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NARRATOR: Column chromatography
is another way

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to separate mixtures.

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The students first pack the
column with a special powder.

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Then, they load the
mixture on top.

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The target molecule is
benzylacetone, and it's

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contaminated with guaiazulene,
a dark blue impurity.

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As the mixture is washed down
the column, the target sticks

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to the solid powder more
strongly than the contaminant,

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so the mixture separates into
two narrow bands which come

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out of the column at
different times.

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As the TAs thought, everyone
is stumbling over the first

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simple step.

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And the problems just
keep coming.

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FRED: The sand staticed itself
all the way up my column, blew

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it out the top and
into my face.

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TENGFEI: Yeah, this is better.

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[Inaudible]

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is on the ball.

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ANTHONY: I should have turned
off the air, but it keeps

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going down.

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So the air's not on?

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ROO-RA: Yeah.

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PROFESSOR: That's not good.

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If there's bubbles in there,
you're in trouble.

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ROO-RA: It's barbaric.

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TENGFEI: You're really bad.

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NARRATOR: How do the students
deal with the pressure?

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PHIL: And so the silica
gel does not...

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[Glass breaking].

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NARRATOR: They break stuff,
lots of stuff.

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How do the TAs deal
with the pressure?

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Feifei gets giddy.

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[LAUGHTER]

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TENGFEI: Like in Chinese
tradition--

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ANTHONY: If we pour together?

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TENGFEI: Yeah.

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ANTHONY: What does it mean?

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TENGFEI: When you are
getting married.

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[MUSIC PLAYING]

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ANTHONY: I'm getting married,
apparently.

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Take two cups and pour them into
each other-- you wait.

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Thank you, finally.

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Are you sure that was
10 mililiters?

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ROO-RA: Yes.

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ANTHONY: Don't steal my--

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(SINGING) The whole day
through, just an old--

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I'm not going to do
that right now.

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No.

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She keeps me grounded.

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[MUSIC PLAYING]

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NARRATOR: And Phil?

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Phil just goes rogue.

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PHIL: You could, like...There
are some people I

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would love to [BLEEP]

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poke with this.

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Just like poke the [BLEEP]

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[MUSIC PLAYING]

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ANTHONY: This is exactly
what I want, right?

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PHIL: Yeah.

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FRED: I'm finally finished.

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IKE: Yeah, this collected
my stuff.

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NARRATOR: But in end, everyone
runs a great column and

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purifies their product.

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ANTHONY: My sample is pure.

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There are no other peaks where
there shouldn't be peaks.

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LINA: Actually, I think my
favorite experiment was the

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flash chromatography.

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ANTHONY: Even though it was
hard, I felt like, I don't

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know, like a chemist, almost.

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HANSOL: I liked watching the
column and putting the air

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pressure down.

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And I loved switching
the tubes.

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It was so fun.

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[MUSIC PLAYING]

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ANTHONY: Oh, I'm not
wearing my goggles.

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That's bad.

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I really should have been
wearing my goggles that day.

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There's no excuse.

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[MUSIC PLAYING]