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Help me, I’m failing chem

What is the hydronium ion concentration of a pH of 3.4?
a. 5.0 x 10^-4 M
b. 4.0 x 10^-4 M
c. 2.5 x 10^-3 M
d. 1.0 x 10^-7 M

User Derek Veit
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2 Answers

4 votes
Trick for the future:
When finding H+ or OH- from pH or pOH, all you need to type into your calculator is:
2nd log - (pH or pOH) to get the answer
For this problem, you would do 2nd log -(3.4) to get an answer of 3.98 x 10 ^ -4 ≈ 4.0 x 10 ^ -4 like the person above said
User Myaseedk
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Answer:

b

Step-by-step explanation:

[H3O+] = 10-pH = 10-3.4 ≅ 3.981 x 10^-4 moles/liter

User Kyuuji
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