The [#H^+#] in a solution is 0.01 M. What is the pH of the solution?

1 Answer
Dec 8, 2016

#"pH" = 2#

Explanation:

The pH of a given solution is nothing more than the negative log base #10# of the concentration of hydrogen ions, #"H"^(+)#, which you'll sometimes see written as #"H"_ 3"O"^(+)#, the hydronium ion.

You thus have

#color(blue)(ul(color(black)("pH" = - log(["H"^(+)]))))#

In your case, the problem provides you with the concentration of hydrogen ions

#["H"^(+)] = "0.01 M"#

This means that the pH of the solution will be

#"pH" = - log(0.01)#

#"pH" = - log(10^(-2)) = - (-2) * log(10)#

Since you know that

#log_(10)(10) = log(10) = 1#

you can say that

#color(darkgreen)(ul(color(black)("pH" = - (-2) * 1 = 2)))#

Because the pH is #<7#, this solution will be acidic.