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Corrosive powers of citric acid s on different metals

I am in grade 10 in Secondary School in Australia, I have been asked to do a research assessment in science. I have chosen to do the effects of citric acid ⇦ this on eBay or Amazon [affil links] s on different types of metals. I would ask you to help in my research

Peter H [surname deleted for privacy by Editor]
- Sydney, NSW, Australia
2003

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A good project would be to make up a known strength of citric acid (say 20% by weight) and leave different metals in different sealed containers. I would suggest using galvanized steel, brass, copper, tinplate, aluminium, mild steel, stainless steel, lead, zinc.

All of these are easily available in most hardware stores. If you have access to any other metals, use them as well. Accurately weigh the samples before you put them in the citric acid and leave them for known times. Dry the samples and reweigh them after set times and plot the loss of weight against time.

I would suggest you think in terms of days, not hours for most metals, but do the experiments and adjust the processes accordingly. It is important to note all experimental conditions. Another thing you could do is to put mild steel into the citric acid , but leave it open to the atmosphere; -will this make any difference to the corrosion rate and explain your answers.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2003

Perform a web search using the following keywords: citric acid passivation citric acid pickling citric acid descaling citric acid cleaning

Toby Padfield
- Michigan
2003

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my name is febi mardianto, who final student from Bandung institute technology Bandung. I have final project about corrosivity of citric acid solution. specimen what I used is aluminum (pure). variables applied on this research are temperature (27C, 40C, 50C) and concentration of citric acid solution (5%-weight, 10%-weight, 15%-weight, and 20%-weight. I have been finished it now. sincerely.

febi mardianto
ITB - Bandung, Indonesia
May 21, 2010