Hi, this is my first post on the forum. So firstly, Hello. I am a late bloomer, in the science community, being 44 and father of two (just about)adults.
Secondly, as per the title. I have searched for but not found an answer. How can I tell when the end point or AN end point has been reached? I have read that the end point is reached when no more HCl(g) evolves. However, with the amount of reflux that happens how can you tell if the gas has stopped evolving? Or is the end point when the reflux starts?
I perhaps should say WHY I want to make HCl(aq). Well I cannot go out to a supplier as my disability means I cannot walk far or drive any more. I also cannot find a supplier willing to sell and post in small amounts, unadulterated quality, to experimenters. Possibly because of what it can be used to make? I was able to buy only H2SO4 in 38% Max or battery acid. So, the reaction is fairly slow in starting and I have to apply 185-190°C in my sand bath.
I have made two macro scale attempts at making HCl(aq). The first attempt the products were a yellow sol and HCl(g). From what I have been able to find on Google, that is what is supposed to happen. The HCl(g) was bubbled through DD H2O giving HCl(aq). I particularly like to watch the formation of the bubbles and them dissolving in the H2O before they can reach the surface . It seems to have made a fairly strong HCl sol. I tested it with a 5mm square piece of Al foil, which was fully dissociated after 2 mins.
The yellow sol I also tested with the Al foil, It dissolved in 3mins. However, I was not happy about the reflux towards the end of the experiment. I don't think any HCl(aq) was drawn into the reaction vessel but it could have?
So, with the second attempt I stopped as soon as the reflux activity started but ended up with a colourless product in the reaction vessel. This colourless sol dissolved the Al foil in less than one min! Have I just concentrated the H2SO4, have I stopped before the yellow product developed, not enough heat, too much heat or have I contaminated my experiment some how?
For the second experiment, the cooled HCl(aq) from the first reaction was used to absorb the HCl(g) from the second to give me a stronger concentration of HCl(aq).
The resultant HCl(aq) is indeed much stronger than before the second experiment. It dissolved the foil in less than 30 secs.
If it's a bit hard to follow my discription of the experiment. Ask me for clarification. I know there are a lot of questions in this post but I really want to understand what is happening in this experiment and why I had two different outcomes.
Any help please.
Larry
Merged post follows:
Consecutive posts mergedI just realised you might wonder why I want HCl(aq) in the first place.
Well, I have no intention of making any narcotic drugs or psychotropic substances that's for sure. Nor indeed any other illicit experiments.
I have purchased A big chemistry set to do some learning. As I am recently divorced and housebound, I wanted something constructive to do with my time. Naturally it requires some HCl(aq) for some of the more interesting experiments. Which again Naturally are not included in the kit.
Thanks for any help.
Larry
Merged post follows:
Consecutive posts mergedBy the way: I used the same volume of H2SO4 in both experiments. However, I think I used more NaCl in the second as there was some NaCl remaining at the end and I don't have a reliable balance.
I know, I know, measure everything and record mass/volume/molarity. But I don't have a balance so cannot.
Any help Please!
Larry