TSR Chemistry Society

I see, this is so interesting that I have a question: does his proved theory of dissociation of electrolytes has explained the working of the voltaic pile and the galvanic cell which were hundred years before invented to name but a few? or are there another scientists who have had the same theory (or a similar one at least?) like Arrhenius before?

I did yes, can't say it was overly successful, none of the planned final steps ever yielded a stable compound.


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Can I PM you to ask more about it? (Not about confidential research info)

Interesting question, when the scientist Luigi Galvani has invented the galvanic cell, he wasn't inventing it on purpose, he was doing anatomy to the leg of a frog in the laboratory and this has resulted to him discovering that when two metals are connected, electrons flow and voltage can be measured and the the voltaic cell is invented afterwards, I think the scientist didn't have a broad explanation at that time of why electrons flow because the concept of dissociation was not yet discovered by Arrhenius but he knew that electrons flow somehow, plus he was a biologist and not a chemist so maybe that's why he didn't discover the concept of dissociation before Arrhenius

So, Arrhenius was really the first scientist who has given - without intending that - an explanation to the galvanic cell and voltaic pile? that is nice. As you mentioned the thing with the legs of frog, there was a doctor by the name of Santiago Ramon y Cajal in the same period who has explained and described how nerve cells work in general, so for frogs too. That is a long time from Galvani to Cajal, no wonder, the methods for researches were restricted at that time (Cajal was able to use a microscope, Galvani not. Cajal was grown up in a secularised period of time, Galvani just in a certain degree...).

Wow, I didn't even know that. It's really interesting how scientists in the past used to discover explanations to things that are not even seen in the naked eye, like how did they even think of these explanations?, when you think about like they're real geniuses, as considering also in the past, there wasn't the equipment that are available now as you said the methods were restricted

As far as I know Cajal has dissected some parts of the brain, sopped in a liquid after that to make the inner of those parts visible on a microscope - and discovered the nerve cells. Even if Galvani would have loved to get to know how the electricity of the frog legs works, he has never get that out. It lasted another century - starting from his lifetime - til the first microscope were produced and used in sciences and laboratories anyway.

Yeah, i think if Galvani had the microscope and the other needed equipment, he would be the first scientist to discover the electrical cell and how it works

Think so too. But even without an explanation of movement of ions, his work, the galvanic cell, was a great contribution nevertheless. Oh did you know that he has had a nephew by the name of Giovanni Aldini who has made experiments about electric current with human corpses?

Really! I didn't know, wow seems his whole family are interested with electricity and human organs! And yeah his contribution to society was beneficial like without him, the galvani cell was not discovered and an explanation is not put

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Hi, I've done all the aqa chemistry a2 unit 4 past papers Does anyone know any good websites or resources for further questions

What's the unit about?

It has kinetics, equlibria, amines, acid and bases, nmr, organic synthesis, amino acids
I just want further questions, like how in maths you can go and do soloman papers

Can someone please explain steam distillation, I can't get my head around it ?

Do you want to know how it works exactly?

Look: there are many different liquids in one, so a mixture. To separate these liquids, the steam generator filled with water is heated step by step first. In the following time, water begins to boil. When the boiling temperature of water is arrived, the water begins to turn into vapour, thanks to the vapour pressure, this steam is moving in an outlet which leads to a round-buttom-flask where the starting product, the mixture, exists. In this round-bottom-flask, the vapoured water (steam) begins to condense, water is liquid in the round-bottom-flask again. After that the water is mixed with the starting product. This leads to a decrease of the boiling temperature of the starting product, that is to say the mixture needs lesser heat to arrive the boiling temperature. When this happened, the mixture in the round-bottom-flask is heated step by step again till the mixture begins to boil and to vaporize. The vapour pressure is causing a movement of this vapoured mixture through an outlet till the vapoured mixture arrives the (closed) Erlenmeyer-flask, where the distillate - the separate liquids of the mixture - is caught. And so, you have separate the mixture into different liquids.

Hope this explanation helps you.