acid question (1 Viewer)

clever angel

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can ne one answer this tricky q'n

a series of ten fold dilutions was carried out on a solution of 0.01mol/l of nitric acid

wat is the minimum concentration of hydrogen ions that can e ibtainedd by successive dilutions of HNO3

ans is 0.0000001 mol/l


thus ph of 7

plzz hsow working
 

LostAuzzie

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Well the best answer I can give you is that because HNO3 is an acid as you keep diluting it you are increasing the pH. The maximum you can reach is pH 7 because that (theoretically although not always the case) is the pH of the water with which you are diluting the HNO3.
 

Dreamerish*~

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Lostaussie is right.

Nevermind the minimum concentration of H+ and focus on the pH. Because you are diluting the acid with water, you cannot possibly obtain a pH of >7 because the pH of water is ~7.

As the acid is diluted, the pH rises, but since the solution can never be alkaline, the maximum pH is 7, when the concentration of H+ is so small that it is not taken into account.

Using the rule [H]+ = 10-pH

[H]+ = 1 x 10-7 = 0.0000001 mol/L. :)
 

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