Magnesium reacting in monoprotic strong acid

[shredder666]

If I have x moles of magnesium and y moles of a monoprotic strong acid (I'm talking about something like 0.03 moles or less of each reactant with the magnesium being the limiting reactant) the there's going to be a noticable pH change right?

Because I remember my teacher showing us the titration curve of a strong acid titrated with a strong base, there was that S-shape (or Z-shape) , where the first few drops of strong base didn't really change the pH at all and then there was that sudden change. Is that going to be the same case with strong acid "titrated" with magnesium?

I'm also wonder how fast, in terms of seconds (a rough estimate), would the reaction be for magnesium metal reacting with HCl, and how complete the reaction will be, is all of the magnesium going to react with the hydrogen gas and not participate in some reverse reaction?

 

[Borek]

Depending on the values of x and y there can be or can be not noticeable change in pH. However, you will not get fast change of pH as in titration, as you will not get pH above 7.

You won't get speed estimate, as it depends on many factors - the most important ones being metal surface and the way solution is mixed. I think it will be up to several minutes if you put a thin Mg ribbon in 1M HCl.

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