Tips for finishing Experiment 3 on time:
Everyone must do experiment 3 individually, however, you can certainly speed things up by planning
ahead with your fumehood “partner”. And check the stopcock on the sep-funnel!!
...
Tips for finishing Experiment 3 on time:
Everyone must do experiment 3 individually, however, you can certainly speed things up by planning
ahead with your fumehood “partner”. And check the stopcock on the sep-funnel!! You should feel a
decent amount of resistance when opening or closing the stopcock. It should not turn with little to no
effort – but at the same time, you should not be struggling to turn it. And be sure it’s closed before you
add your solutions to it.
Part A:
The 1.0g of mixture the manual says to weigh out – this is approximate. If you have 1.231 g, that’s ok –
just be sure to record the mass in your notebook.
Each of you will need 15-20 mL of ether. You will also each need 30 mL of 2M HCl, and 15 mL of water.
Recommendation: While one of you weighs out your sample, the other person can get 40 mL of ether in
an Erlenmeyer flask and put parafilm or a stopper on the flask. Bring it back to the fumehood. Label
using a wax pencil or have some sort of paper label. Then, the second person can weigh out their sample
while the first person can get 60 mL of the 2M HCl, and bring it back to the fumehood (label!). For the
water, get a wash bottle filled and have it in your fumehood. This final 15 mL of water is not an amount
that needs measuring – it’s an estimate. ***
If you see a huge lineup for the HCl or ether, look at the second section to Part A:
Each of you will need 30-35 mL of 10% NaOH solution. Take a flask and get about 75 mL of 10 % NaOH
solution. Bring it back to your fumehood – again, make sure you have things labelled somehow.
When adding the hydroxide to the aqueous phase, the manual mentions to check the pH to make sure
it’s 11-12. There’s no need to check the pH until you’ve added the suggested amount of hydroxide.
Once you are at this point, you have almost finished Part A. You just need to filter and dry your
chloroaniline, get a yield and test the melting point. If you want, you can even leave this for later and
move on to part B now. Rinse your flasks that had HCl and NaOH with water because you will need clean
flasks for the next section.
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