Questions tagged [corrosion]
For questions about the process of corrosion or protection of metals from corrosion.
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Clarifying question about chloride ions, water softening & corrosion
I have a question regarding the use of NaCl as a water softener.
Recently i was asked to comment on a series of test results from a water softening device were a lot of corrosion had occurred post ...
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What materials are resistant to hot chlorine?
I'm looking to do an experiment involving hot chlorine gas (900 Celsius), however at the moment the only material I'm aware of that could cope with this is Hastelloy's C-22 alloy. What other ...
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Is "stainless" a bulk or a surface property of stainless steel?
In particular, if I cut a block of stainless steel in half, would the newly formed faces be stainless as well?
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What happens to the carbon in carbon steel when it rusts?
Carbon steel is iron containing some carbon in various forms of iron carbide.
When it rusts (oxidises), the iron becomes part of all kinds of crystalline and amorphous iron oxides and hydroxides, ...
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"Hairy" corrosion on anodized alu-part in water
I got a water tank with a mechanical assembly in.
The assembly consist of parts of anodized aluminium mounted on stainless steel plates (AISI 304). This is submerged down in fresh water. The tank is ...
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The effect of nitric acid on the rate of corrosion of copper
I conducted an experiment concerning the rate of corrosion of copper when submerged in three solutions. In the first solution, 5ml concentrated nitric acid and 10 ml distilled water was added. In the ...
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How do metals split the oxygen double bond during corrosion?
For a metal like $\ce{Mg}$ to corrode into $\ce{MgO}$, the double bond in $\ce{O2}$ must break. Since the dissociation energy of $\ce{O2}$ is 500 kJ/mol, using estimates from the Boltzmann ...
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What are some easily-undertaken reactions that will precipitate or restore the iron from rust, in a non-lab context?
Unusually, this question arises in a DIY context rather than a chemistry one.
I'm doing some work in my garden with reinforced concrete (a retaining wall against a high bank of soil). As some will ...
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Rate of cathodic reaction vs Tafel slope
One of my reference engineering books says that for the cathodic protection process (in seawater):
Al $\rightarrow$ Al$^{3+}$ + $3e^-$ (anode, setting the protection potential at about -900 mV SCE)
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Why do old black and white photos fade?
I understand why photos based on organic dyes would fade (discussed previously). But photos based on metallic silver fade as well such as like the one shown below. As a metal (a fairly stable one at ...
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Brass - is this corrosion or oxidation and why did it happen?
I have bought a new brass Y-split water valve which is plain brass but inside is a more polished one, it was packed nicely and I opened it 2 days ago, washed it off with water for some reason, then ...
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Can gold cause tin or other metals to corrode?
I stumbled upon the following article while trying to identify some old RAM modules:
https://www.techrepublic.com/article/quickly-identify-ram-chips-with-these-tips/
In the article, it mentions the ...
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Low-cost nontoxic corrosion inhibitor for steel exposed to hydrochloric acid
It seems that many commercial descaling solutions designed to remove scale (calcium carbonates, etc that form on water heaters) are a simple combination of an acid and an acid corrosion inhibitor for ...
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What happens electrochemically when bird droppings corrode cars?
I think the metal of the car first goes through an acid corrosion, followed by an electrochemical corrosion. First, the uric acid in bird poop corrodes with iron: 2Fe+C5H4N4O3 -> C5N4O3Fe2+2H2. Then, ...
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How Can I Induce Corrosion Electrochemically?
I'm very interested in measuring corrosion in metal alloys, particularly in salt solutions. I understand metals corrode over time, however, I was wondering if it's possible to electrochemically "speed ...
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