On 9 June 2023, I asked ChatGPT about a discovery I made regarding copper plating, which
I made in my home chemistry laboratory when I was about thirteen years old. This would
have been in the late 1960s. Anyway, at that time, I was really fascinated by chemistry. At
one point, having no idea what I was doing, I was mixing up three chemicals to see what
would happen (I did take protection of some sort in those days.) The three chemicals were
hydrogen peroxide, copper sulfate, and Potassium Bitartrate (Cream of Tartar). The copper
sulfate I got out of my chemistry set, but, one can purchase copper sulfate for home use.
Anyway, I mixed the three chemicals together and it boiled up hot (as I remember) [the
reaction was exothermic], then I let it cool of and for some reason I placed a galvanized
nail into the resulting solution and left it. When I came back to it many hours later, the
nail had been beautifully copper plated. I explain the basic results I got with this proceedure
to ChatGPT and asked it to comment on it, which it did. I don't know how accurate its advice
is, but there should be some wisdom in there. I was curious how well ChatGPT can reason
within the realm of chemistry. The most poignant aspect of my home experiment to this day
is the beauty of that copper-coated nail, as if it were of the same shinyness as a brand
new copper penny.
Patrick:
Long ago I mixed together three chemicals: hydrogen peroxide, copper sulfate, and Potassium
Bitartrate and discovered that if I left a galvanized piece of metal in the resulting
solution that the copper in solution would very effectively copper plate the metal. Can you
comment on this from the viewpoint of a chemical analysis, and from the viewpoint of a possible
commercial process?
ChatGPT:
From a chemical analysis viewpoint, the reaction you described involves several processes.
When hydrogen peroxide (H2O2) is mixed with copper sulfate (CuSO4) and potassium bitartrate
(commonly known as cream of tartar), several reactions occur.
The hydrogen peroxide acts as an oxidizing agent, providing oxygen for the reaction. The copper
sulfate dissociates in water to form copper ions (Cu2+) and sulfate ions (SO4^2-). The cream
of tartar, which contains tartaric acid, reacts with the copper ions to form a complex, soluble
compound called copper tartrate. This complex is more stable in solution compared to copper
sulfate, allowing the copper ions to remain in solution rather than precipitating out.
When a galvanized piece of metal (usually steel coated with a layer of zinc) is immersed in this
solution, the zinc acts as a sacrificial anode. It undergoes oxidation, releasing zinc ions (Zn^2+)
into the solution. Meanwhile, the copper ions in solution are reduced and deposited onto the
surface of the metal, forming a copper coating through the process of electroplating.
From the viewpoint of a possible commercial process, there are a few considerations to take
into account. Firstly, the effectiveness and quality of the copper plating may depend on the
concentration of the chemicals, temperature, and duration of immersion. Optimization of these
factors can result in a more efficient and consistent process.
Secondly, the sustainability and cost-effectiveness of the process should be evaluated. The
chemicals used, particularly copper sulfate, may have associated environmental concerns and
cost implications. It would be important to assess alternatives that are more environmentally
friendly and economically viable.
Furthermore, scalability and automation of the process should be considered for commercial
applications. Industrial electroplating processes typically involve precise control over various
parameters, such as current density, plating bath composition, and agitation. Developing a
controlled and reproducible process that can be implemented on a larger scale would be crucial.
Overall, while your discovery provides a basis for copper plating, further research, development,
and optimization would be required to establish a commercially viable process that meets industry
standards in terms of efficiency, sustainability, and cost-effectiveness.
Patrick:
I did not use any anode or cathode in the copperplating, which distinguishes the process
I discovered a little. Can you comment on this facet?
As I reread this follow-up query I made, I feel that it is somewhat ambiguous. Somehow
I wanted to let ChatGPT know that I was not attempting an electroplating process, but it
seemed to get that message anyway. It seems to be able to 'understand' even ambiguous
content. On the other hand, when ChatGPT just assume from the start that I had performed
an electroplating process, it got that assumption wrong. So, should ChatGPT have asked me
if I had been using an electroplating process in my 'experiment'?
ChatGPT:
Apologies for the confusion. If you achieved copper plating without using a separate
anode or cathode, it suggests that the galvanized metal itself acted as both the substrate
(cathode) and the source of copper ions (anode) in the electroplating process. This phenomenon
is known as "self-plating" or "autocatalytic" plating.
In the case of galvanized metal, the zinc coating on the surface contains zinc metal (Zn) that
can serve as a source of zinc ions (Zn^2+) in the solution. When the galvanized metal is
immersed in the copper sulfate solution containing hydrogen peroxide and cream of tartar,
the zinc coating undergoes oxidation, releasing zinc ions into the solution.
The released zinc ions then react with the copper sulfate and cream of tartar in the solution,
forming a soluble complex, copper tartrate. This complexed copper is reduced at the surface
of the galvanized metal, resulting in the deposition of copper onto the metal.
In essence, the galvanized metal acts as both the source of metal ions (anode) and the
substrate for copper deposition (cathode) in this self-plating process. It is a unique
feature of the system you discovered, and it simplifies the setup by eliminating the need
for separate anodes or cathodes.
However, it's worth noting that the efficiency and quality of the self-plating process
may depend on factors such as the condition and composition of the galvanized metal, as
well as the concentration and ratio of the chemicals used. Optimization of these parameters
may be necessary to achieve consistent and desirable copper plating results.
If you are considering commercial applications, it would still be essential to further
investigate and understand the intricacies of the self-plating process, as well as its
limitations and potential variations in performance. This knowledge will enable you
to develop a reliable and reproducible process suitable for industrial-scale applications.
Okay, back to me (Patrick). I apologize that I did not keep accurate records of the
proportions of the chemicals that I used during this "experiment." Unfortunately,
this process has languished in total obsurity for half a century and I wanted to
publish it here in the hopes that one of two things would happen. First, ChatGPT
would tell me that the process is already well-known and so then that would be the
end of my involvement with it. Or, second, that someone with a chemical background
and some curiosity will read this chat and decide to reproduce the experiment for
him or herself. If you do, I wish you success.
As for how ChatGPT did as a chemistry professor, I'm impressed. I don't know how
accurate its explanations were or how good its advice is, but it all sounded
reasonable to me.
PS: My memory is not clear on this, but I seem to remember that my motivation to
placing the galvanized nail into the solution was to see if crystals would grow
on the nail, as it had when I made the alternative solution by replacing the copper
sulfate with iron sulfate. Perhaps I ran out of the latter, so I had to use the former.
And, as a result -- Bang! -- quite an interesting discovery.