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Problem 139 Hard Difficulty

Cocaine $\left(\mathrm{C}_{17} \mathrm{H}_{21} \mathrm{O}_{4} \mathrm{N}\right)$ is a natural substance found in coca leaves, which have been used for centuries as a local anesthetic
and stimulant. Illegal cocaine arrives in the United States either as the pure compound or as the hydrochloride salt $\left(\mathrm{C}_{17} \mathrm{H}_{21} \mathrm{O}_{4} \mathrm{NHCl}\right)$
At $25^{\circ} \mathrm{C},$ the salt is very soluble in water $(2.50 \mathrm{kg} / \mathrm{L}),$ but cocaine is much less so $(1.70 \mathrm{g} / \mathrm{L})$
(a) What is the maximum mass $(\text { g) of the salt that can dissolve in }$ 50.0 $\mathrm{mL}$ of water?
(b) If this solution is treated with NaOH, the salt is converted to cocaine. How much more water (L) is needed to dissolve it?


a) 125 g salt
b) $65.6 \mathrm{L} \mathrm{H}_{2} \mathrm{O}$


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Video Transcript

So we're keeping coking and cocaine hydrochloride sort. So for these Ah, we have, Ah, Two different reconstituted informs. So we're cocaine. You naturally, it's organic days. So can we have your hydrochloric acid if I, um assault. So they have tiffin soul ability for cocaine. We have 1.7 grams per liter and in fort, um ha ha Joke. Always thought because the salt, please. I only compound so he can be these off for 2.5 kilogram for the Italian border. Okay, so what would four part able with the mass mass off coking sauce? Cocaine sort capitalise Soviet 50 milliliters of water. Okay, so we know that the soap it is 2.50 Q graham per liter. And then we we should convert that back Thio Um um Graham And also, um, neater guardian of the militar. But let's still do the conversion verse. So we have 2.5 kilogram. So 2.5 kilograms essentially yuko suits to 5 25 100 gram per liter. This would be a saw bitsy and then for our of volume, we have 15 minutes. We just convert that to ah little you goes to soup on civil five litter. Okay, so we're going to multiply. Um, this too. Um, number together Heisman by them. And then we should be able to find that the massive chemical softening 50 minutes of water as well, Because the 1.5 square 1 25 grand. Okay, so part B. Ah, for you, we have a solution. I mean, decision from part, eh? That's going on. Twitter. We have sodium hydroxide, and the song is converted. Thio. Um okay. And how much more water we need in order to Ah, the Soviet again. Okay, So, first of all, we have won 25 graham off the sort. And then when we are going to add a sodium hydroxide, that's so we become coking again and you can see that. Ah, so ability. We change because we have making us assault ionic salt to become a neutral compound again. So for the salt Ah, really know There's 2.5 kilogram per liter and there's all bitty for cocaine is 1.0 graham 70 grams per liter. Okay, so we have ah 1 25 gram in a 50 min it'sa or re convert that she'll be syrup on Ciro five little solution, and they're going to treat with, ah, sodium hydroxide. Okay, so for this question, I believe, uh, we can we have to assume that when we asked him hydroxide the boy doesn't change your mind doesn't change. Um, so because this just didn't have enough information. Okay, So assuming that we just somehow turned a solution to become basic and then all the salt, they become co king again. So what we have at the end of the days that we have won 25 well of our cocaine. But dina 50 militar horse solution or the other world? We have syrup on 75 zero point, um, civil five litre off solution. Okay, But I can feel assaulted here. Too small. Ah, this volume cannot be these off with 1 25 grand work. Okay, So Okay, so if we want to you say tees off off the 1 25 game Oh, cocaine. How much volume of water do we need? Okay, so ah, volume needed. I mean, the total volume. We're looking at the total volume t means total total volume. Lead it. Ah, we will have our 1 25 gram. Ah, some everything. Salto Coke. Okay. Divided by 1.7 Quimper litter. So when we're going to Ah, do, ah, find out the actual volume. We're going to the final that it should be around 70. Free porn. Ah, five, uh, litter litter. Uh, have you focus on the, uh, Mr Cyril? Okay, so, um, we need seven. Thief, 3.5 litre off solution. You know, it's it's too full of yourself. All the cocaine. We have won 25 that. So the excess of the H one volume we need we have our target call volume minus our initial volume. So we have 75.5 months. Irresponsible. Five. When we have 70 free pulling four five liter required to do so far.