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I've been stuck on this for ages, can anyone help a nigga out ?
A solution of 1-hexanol was produced in the following manner: A stock solution of 1-hexanol was formed by weighing 1.501 g 1-hexanol into a 10.0-mL volumetric flask and the flask was filled into the mark with chloroform. 1.5 mL of this stock solution was pipetted into another 10.0-mL volumetric flask and filled to the mark with chloroform.
Calculate the concentration of 1-hexanol in the second volumetric flask in mg / mL.
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1. Find the Normality of stock solution:
MM 1-hexanol = 102.17g/mol
1:1 disassociation ratio between 1-hexanol and chloroform means that molarity = normality
So, treat chloroform as you would 0.01L water.
1.501g (hex) / 102.17g/mol ~ 0.015 mol (hex)
Get the molarity:
0.015 mol (hex) / 0.01L (chlo) = 1.47 (M) molar stock solution.
2. Sample solution molarity after 0.0015L diluted to 0.01L
How many moles of (hex) do we have in 1.5mL of sample:
1.47 (mol hex/ L chlo), there are 0.0015L chlo first so:
1.47 mol/L * 0.0015L = 0.002205 mol hex
We aren't adding more hex so:
0.002205 mol hex / 0.01L chlo = 0.2205 M sample, we still need it in mg/mL.
3. Unit adjustment:
0.002205 mol hex * 102.17g/mol ~ 0.2253 g hex = 225.28 mg hex
Put everything together, you got:
225.28mg/0.01L or 225.28mg/10mL
Divide by 10 to get your final answer. I did most of the work so figure the last step out.
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>>277782
>tries to resist angrily suggesting a different field
>fails
Dude, if you can't do the most basic of quantitative chemistry (stoichiometry), then you need to gtfo of whatever courses your taking in STEM. All that happens is it gets harder to understand, and you will be easy competition for people like me who have been passionately studying chem and bio for at least a decade before entering university to get a job in this stuff. Raking through all of you is annoying in the long run, so fuck off and go do psychology or something that doesn't require precise results.
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>>278027
Why do you assume he's a STEM major? Most liberal arts colleges require all students to take a couple of science courses regardless of major.
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>>278031
You don't take chemistry involving normality unless you're a graduate in BIO/ENVS, or you're undergrad major is CHEM. Only other possibilities being a CHEM minor, or a dumb kid looking for something more interesting in life. I can stand behind the latter, if that is OPs case.
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