Question

The pH of a fruit juice is 2.5. Find the hydronium ion concentration, [H3O+], of the juice. Use the formula pH=-log[H3O+]

Answer 1

\[2.5=-\log[\text{H}_3\text{O}^+] \]

This log is in base 10, so use the property of logs:
\(a=\log_b(x)\) means \(b^a=x\)

If your log is base 10, then \(b=10\) and we don't write the subscript, so
\(a=\log x\) means \(10^a=x\)

If the above formula is confusing, just try imagining that you are substituting \(\text{H}_3\text{O}^+\) by "\(x\)"

so,
\(2.5=-\log x\)
\(-2.5=\log x\)

Can you figure out the rest? I.e. how to solve for x?