How Does One Find the Right Concentration of Sulfuric and Nitric Acid That They Need?

Some of these may help.

How to Calculate the Concentration of Ions in a 0.010... | Sciencing

Why do we use the mixture of Nitric acid and sulphuric acid in... - Quora

Reaction Product of Nitric acid and Sulphuric acid

Environmental study at this level is well beyond your grade level....You would first need an environmental study of the region you are designing materials for, then you would need an advanced degree in chemistry to understand it...

Read the article at this link, and tell me how much you understand of it...

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2015JG003121

If you understood that and are willing to go through all steps necessary, then go for it....

...on the other hand...

In my opinion you would be better off just using saltwater as a corrosive...

You can kick it up a notch with ultraviolet light added in to the mix....

https://www.westpak.com/page/reliability/reliability-uv-accelerated-weathering

SE:

Try not to be so discouraging. This is one of my competition students, and I am advising him. I suggested he check here for advice. It IS NOT beyond his abilities for the competition he is engaging in. But he does need some links I don't have, and some exposure to the forums, in order to obtain the info he needs, and to find out, as I have, how helpful you guys CAN be.

Thanks.

Micahd02,

SE's comment in and of itself is not discouraging. The comment encourages the student to enbark on a project with a level of difficulty likely to provide the most benefit for their current skills/understanding. The comment wasn't actually discouraging until you labled it as such.

Sulfuric and nitric acid also be far more dangerous than salt. What benefit justifies the added risk of injury?

I tend to agree, but not having personal knowledge of the situation, I will defer judgement to Micahd02...

Acid rain is defined as rain having a ph of <5.7....so get some water and add equal parts nitric and sulfuric acids(probably just a few drops per gallon)....Wear your gloves and goggles and proper mask...test periodically until your ph level drops below 5.7...good luck

ref....

https://www.sciencedirect.com/topics/earth-and-planetary-sciences/acid-rain

This idea is on the right track, but since this is an accelerated weathering scenario, it might need to be a lower pH.

Another possibility is to make up various solutions by weight of each acid, expose the samples ("coupons") to each, and examine the amount of corrosion.

Salt spray testing, as you mentioned, could be a good source of preliminary info. The OP might be able to find the protocol for something like UL testing of NEMA 4X (corrosion resistant) electrical panels.

Well this seems to be a structural test, I would imagine with several identical models built, and then a comparison of some with protective coatings and some without, and then submitted to some sort of stress until structural failure, then a comparison of force withstood by each...Then conclusion of which coatings were most effective...That's why I don't see why the corrosive element is important...in any case we have limited info as to the scope of this project...

https://www.cgtrader.com/3d-models/architectural/engineering/electric-towers-17-pieces

I agree that a good test would be exposing the materials to various concentrations (pHs) of the acids, possibly for different time intervals. If you can show a relationship between concentration and time of exposure, you may be able to extrapolate the effect of acid rain over a longer period of time.

One thing I do remember from Chemistry Lab... Add acid to water, not the other way around, especially sulphuric acid. Considerable energy is released when concentrated sulphuric acid touches water!

My thanks to you for this. Jadon will be working in a properly equipped wet lab with a full fume hood, safety goggles, gloves, and respirator, as well as experienced adult supervision. His primary instructor, his 10th grade science teacher, and a good friend of mine, is well known to me. We judge and tutor science fair competition for the state of Virginia, and are in constant communication about all of our student's work.

The reason I am Jadon's primarty tutor and guide in this is that it is a Physics application, under the rules of the competion, and my friend, Jadon's daily science teacher, is a specialist in biological studies. So he hands me his physics competitors. Unfortunately, while either of us could supervise Jadon's lab work, pure chemical research is neither of our strongest points. Hence I pointed him here as part of his research trail, knowing the breadth of knowledge and willing minds present.

Thank you both, again, for the pointers.

"Environmental study at this level is well beyond your grade level...."

Perhaps, but congratulations, Jadon, on not wanting to be a cookie cutter student.

Good luck with your study, and with your studies.

I think that some photographic and perhaps even real samples of actual structures that have severely degraded or failed after prolonged exposure to the environment would be important to this project to more fully illustrate the real life effects of pollution on building structures...certainly some of the most poignant of which is loss of great art and sculptures...

...sadly there is no lack of examples...

https://pubs.usgs.gov/gip/acidrain/5.html

Hello Jadon and welcome to this forum and also thanks for making it clear that you are a student seeking assistance/guidance.

I have supervised environmental exposure laboratories for over 28 years. While the laboratory work that we did was for automotive components, we often found it necessary to accelerate the testing to be able to extrapolate results. Conducting a five year test would mean delaying the vehicle release for production by five years.

We thus developed accelerated methods of testing by using a progression of more extreme exposures than would normally be observed.

We also needed the tests to be able to be repeated at future times.

You seem to have already selected the effect of acids as your source of degradation and others here have provided links to information about observed atmospheric concentrations, but if you stick with those your experiment may take decades as opposed to months.

Maybe you develop a test where your samples are subjected to a "stress" and simultaneously exposed to the reagents in different concentrations until failure to determine a deterioration curve for each material so that you could extrapolate the response to the reported atmospheric concentrations.

You may need to investigate how the pH scale works so that you get a linear scale for the exposure. You might like to use exposure levels of 10x, 100x and even 1000x initially.

You might even then test some "protection" treatments or alternative materials to be able to report their impact. There are some special "acid resistant" concrete formulations used for sewer infrastructure specifically because of exposure to Sulphuric Acid.

Enjoy the project. I was once mentor for some students in Manhattan for their school science project. For me that meant phone calls at 2am to talk to them in class.

^{J an E:}

^{GA from me. This is most helpful advice. As is nearly everything said here. But I'll let Jadon speak for himself in further explanation.}

micahd02 & Jadon,

I agree with the suggestions from J an E. Let me also add: a quick Google search said the pH of acid rain was in the vicinity of 4.0. For an accelerated test of your samples, you would need to use a lower pH (more acidic), and could probably test for rates of corrosion or degradation by solutions sprayed onto the test surface on a timed intermittent basis (allows for air exposure that mimics the normal exposure), separate tests using solutions that contain only Nitric Acid, only Sulfuric Acid, and a mixture of the two--all with a pH that has possibly been buffered to a constant value such as 3.0 (or gets tested and adjusted regularly to a set pH during the experiment). Since a Nitric Acid solution at 0.01M concentration has a pH of approximately 2.0, you are dealing with a fairly dilute solution. However, good lab practice and safety are all needed.

I imagine part of your research will be to learn the measured concentrations of dissolved nitrogen oxides or dissolved sulfur oxides in rain both closely downwind from a typical source (such as a power plant) as well as in a more typical location.

Have fun and learn a lot from your experimental design and results. Remember that the whole "scientific method" includes a hypothesis, an experiment, and an analysis of the results. Your project does not have to have the results you expect--the analysis is a significant portion of how the judges will rank your work.

JMM

When considering ways to accelerate effects, it is worth noting that paradoxical effects on corrosion rates from increased concentration of acid can occur. Nitric acid for example can passivate metals at higher concentrations leading to lower rates of corrosion for hugher concentrations.

The various corrosion mechanisms and factors suggested in the comments are great. It would probably be worth including some review the importance to corrosion of stress and stress risers, temperature and temperature swings, fatigue, errosion, intermetallics, liquid metal embrittlement, pitting , cracks and crevaces, as well as particar important species like: those containing or comprised of oxygen, chlorine, sulfur, hydrogen, etc.

Low Hangin' Fruit and Planning a Career in Technical Communication. ....8)... <-Shmoo Smiley

"The most common source of acidity in water is carbon dioxide."

I hope you are not ignoring the elephant in the room. In addition to being a primary source of aqueous acidity, water with dissolved carbon dioxide is very easy to obtain. While you are waiting for access to your more exotic acids you can buy some generic or store brand unflavored sparkling water or club soda at your local quicky mart and start designing your schmoo tests.

If you do not know what a schmoo test is, you should research that word, because it is really good for entertaining those who will be bored by clinical type science. The schmoo appeared in some comic strips and you will generate interest if you can tell the stories which revolve around the schmoo term. A crowd reading your comics is hard to distinguish from a crowd absorbing your scientific musings at a public event.

Now, back to the science and some easy schmoo dimensions for your testing. You can take some concentrated club soda in a bunch of small cups, toss in some metal material variations such as iron, cast iron, high carbon steel, galvanized steel, stainless steels(8/18, and other alloy variations), rebar in concrete with cover, rebar sticking out of concrete, rebar and a lump of concrete in the same cup, .... You can cover aluminum, anodized aluminum, aluminum/magnesium alloys,... You can explore another schmoo dimension by diluting your club soda with various quantiites(do it by weight) of distilled water. At the risk of having a flag thrown for "piling on" you can use various concentrations of tap water with whatever fluorides, chlorines, chloramines, etc. your local water district uses. You could evaporate tap water to achieve non-volatile concentrations of water additives which are higher than nominal. You could explore mixes of metals such as aluminum siding material applied to galvanized steel stud metal.

Once you have some experience with less dangerous acid you can repeat your test matrix with far fewer samples with low concentrations of the hazardous stuff to see how it affects the shapes of your schmoo charts. If there are few and inconsequential variations to your schmoo then you do not have to do so many tests or tests at higher concentrations with your dangerous stuff thus reducing the quantity of difficult to obtain chemicals you actually need to do a good scientific study. Documenting how you avoided expensive and hazardous chemicals as much as reasonable to demonstrate your science will look good in resume content for applying for a job at any professional laboratory since the cost of running acceptable tests is often a concern for tasks they might want you to perform. Hazardous materials use raises the cost of experimentation whether or not the actual material used is intrinsically expensive.

Observing the evolution of the shape of your schmoo curve can be a good place to develop and expose your skills of observation which are essential to designing good probative experiments. If I have used any esoteric words besides schmoo in this post about which you have any doubts about their meaning in this context, you will be wise to research their deeper meaning in a scientific laboratory context as homework. I encourage any of the other lurkers on this thread to provide additional relevant vocabulary. I also recommend making sure of your use of then/than simple/simplistic and similarly chronically misused words since fluent documentation is often a skill sought by judges and interviewers. Your original post indicates good command of English so you can probably can concentrate on more obscure terms which have niche meanings in scientific documentation. I have included the discussion of commonly misused terms largely for the benefit of other, less sophisticated, readers.

BTW, I am not the oracle for English competence. As, you may have noticed above, I have a weakness for overly complex sentence structures among other faults. I might also warn against use of unnecessarily esoteric vocabulary when simple language will suffice. I particularly like conceptually onomatopoetic comments which practice often annoys those who focus more on gramma[on my mother's side, who used more strictly correct grammar] than I do.

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thewildotter

All good SE.

I knew there's a reason I sent him to you guys for help.

Standard Catalogs, Note Cards, Bibliographies, and Attributions

Yes, I was hinting at "electrolysis" when I mentioned aluminum siding on steel studs. Thanks, SE for providing the OP with "electrolysis", "sacrificial anode", "mitigate", for vocabulary development. Your being from Florida reminds me that "aerosols" are often implicated in structurally important corrosion. There have been documentary videos on iron from the Sahara contributing to coral reef creation off the coast of the Americas demonstrating a long distance, structurally positive, impact of chemical migrations. Interface corrosion, such as where metals exit standing water is also a fertile topic. I see that it won mention in SE's excellent link of 8 forms of corrosion under "crevice corrosion." This is a good example of a non-obvious name for something which works well across all scales. Knowing this more generic name for the phenomenon facilitates researching additional examples and explanations of the situation and integrating a discussion of it into the overall schmoo analysis of the topic of interest.

Research and understanding advances much more rapidly if one initially collects the germaine vocabulary. My Library Science friends call this the "standard catalog." Funny how cross-discipline technology serves as a cognitive accelerant as a kind of opposite of the confused language curse of the tower of Babel. It strikes me that the arduous high school assignment of creating "note cards" for a research topic structures this process of developing a "standard catalog" on the topic, stealthily forcing the inherent maturation of a germaine vocabulary on the researcher. "Google searches" may be the modern equivalent of a "note card" task in maturing your topical vocabulary and your topical set of browser "bookmarks" may be the visible work product. Web surfing seems considerably less tedious than generating a shoe box full of note cards, but it is probably wise to perceive the germaine vocabulary as the real value in either case. Isolating, organizing, and retaining the bookmark set as a specific item of value seems appropriate. Conveniently providing such a topical bookmark set as an online bibliography to those who demonstrate deeper interest is similar to providing a bibliography on a research paper. Unfortunately, dead links (404 errors) are even more likely than being unable to locate a book mentioned in a paper bibliography.

To the OP, providing an online set of bookmarks is a modern equivalent of a bibliography and will distinguish your presentation relative to those which do not provide one. SE seems to be aware and has provided a nice link to a very relevant web page for your inclusion in your "bibliography." Integrate and perhaps even attribute it. It documents your reaching out to the community and receiving valuable input to your research collaboration. GA to SE.

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thewildotter

Maybe even a YouTube video is in order....It would be nice to make a youtube video of your efforts and findings, a study of current state-of-the-art measures being utilized in today's infrastructure...and possibly future projections....

https://www.nationalgeographic.com/environment/global-warming/acid-rain/

And from me, a GA to tjewildptter. You've brought ME a better appreciation of the value of what was always a tedious task.

https://www.youtube.com/channel/UCrvfiHNDS_QI-FgKQSmTITQ

An hour or two browsing NCASI.org might give you some good ideas regarding reagent strength and test procedures. And I'm sure you've already checked the EPA's website and that of your state's Environmental Department?

Jadon,

If you are interested in seeing the long term effects of sulphuric acid accelerated, schedule a tour of a coal fired power plant that has a Flue Gas Desulphurization ( a wet scrubber). if there is any age on the scrubber you will see advanced decay of structural steel and etching of concrete. You may also see some structural steel that had a proper coating applied that appears untouched. The staff at the generating station should be able to tell you the approximate age of the corroded items. Typically a scrubber will have parts of the original construction as well as upgrades that were added years or decades later. You could document what you see and then try to duplicate it in the lab. Good luck and have fun. Don't be afraid to discover things you didn't expect to see.