How to Calculate the pH of 0.001 M NaCl?

[AdnamaLeigh]

How do you calculate the pH of 0.001 M NaCl? I was thinking of doing NaCl + H2O ---> HCl + NaOH but I don't know where to go from there if that's even the right step.

 

[mrjeffy321]

Sodium Chloride is a strong electrolyte meaning it will disassociate completely in solution.
Strong electrolytes will not affect the pH of the solution as the acids / bases they form are also strong electrolytes.

A NaCl solution of any concentration should have (ideally) a pH of 7.


NaCl (aq) + H2O (l) ---> HCl (aq) + NaOH (aq)
HCl (aq) + NaOH (aq) --> NaCl (aq) + H2O (l)

 

[Borek]

A NaCl solution of any concentration should have (ideally) a pH of 7.

ionic strength and activity coefficients

 

[GCT]

The topic of ionic strength is practical with buffer preparation, however, I don't believe that it's an important factor with regard to the pH in this situation.

 

[siddharth]

AdnamaLeigh, you might also want to take a look at this thread.
https://www.physicsforums.com/showthread.php?t=124602"

 

[Borek]

The topic of ionic strength is practical with buffer preparation, however, I don't believe that it's an important factor with regard to the pH in this situation.

It is an important factor in every solution containing ions. Even if it doesn't change numerical value of pH in this case, you can't assume that addition of neutral salt never changes pH of the solution.