Question 1046634
 pH = -log10[H+] Find the [H+] if the pH = 8.4. 
8.4 = -log10[H+]
H+ = 10^-8.4 = 3.9811*10^-9
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Cheers,
Stan H.
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Possible answer:
a. 3.98 x 10-8
b. 2.51 x 10-8
c. 3.98 x 10-9
d. 2.51 x 10-9