Questions tagged [corrosion]
For questions about the process of corrosion or protection of metals from corrosion.
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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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Does concentration of salt increase or decrease rate of rusting?
I want to know whether increasing the concentration of salt, specifically $\ce{NaCl}$, increases or decreases the rate of rusting. There are conflicting theories that explain opposite outcomes:
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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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Why does the corrosion of a steel nail develop iron ions in the ends of the nail and hydroxide in the middle of the nail?
We did an experiment in school where we put a steel nail in a solution consisting of:
1 g agar;
100 ml water;
100 ml indicator solution (which gets blue whenever $\ce{Fe^2+}$ is created and red when $...
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Do I need to 'neutralise' iron/steel/metal with a base after removing rust with acid?
I've never asked a question here before but these forums seem to have some extremely knowledgeable people so I thought I'd give it a try. I know it's a 1st grade question but I honestly don't have the ...
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Creating resilient (non-brittle non-water-soluble) verdigris (blue-green copper patina)
First off, I checked and there are indeed a number of questions on copper patinas, but none which deal with resilience.
Context
I own a number of copper writing utensils, which I'd like to get a nice ...
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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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Rusting in every other bar
I have noticed that, when a structure with bars (such as a gate or a grate) develops rust, this sometimes happens differently across the bars. In particular, it seems that the bars are alternatively ...
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Does 99.8% acetic acid cause severe skin burns like formic acid?
I've so far handled only concentrated fuming nitric, sulfuric & hydrochloric acids from the inorganic side. Even during an accidental spill on the hand I did say only the $\ce{HNO3}$ affects the ...
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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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Choosing electrodes for corrosive environments
Background
I'm building a watering robot for my household plants. For the purpose of measuring the moisture content of the plant I intend to use a resisitive approach where I pass an electric current ...
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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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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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Nichrome alloy corrosion at high temperature
We are currently using a nichrome (80/20) wire based heater to surround a sample chamber that we wish to heat by radiation. Maximum sample temperature is 400degC in an atmosphere of air that may be ...
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When we are looking for volts vs SHE, is it that the potential of the element is compared to hydrogen potential?
I'm new to understanding this aspect of electrochemistry and only just now refreshing my memory of high school chemistry for a specific purpose. If I've worded the question or anything else ...
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