the equation for the ph of a substance is ph = -logh⁺, where h⁺ is the concentration of hydrogen ions. what…

the equation for the ph of a substance is ph = -logh⁺, where h⁺ is the concentration of hydrogen ions. what is the approximate ph of a solution whose hydrogen ion concentration is 2×10⁻⁹?\n1.0\n2.9\n8.7\n9.3
Answer
Explanation:
Step1: Substitute the given value.
Given $[H^+]=2\times 10^{-9}$, substitute into $pH = -\log[H^+]$. So $pH=-\log(2\times 10^{-9})$.
Step2: Use logarithm property.
Using the property $\log(ab)=\log a+\log b$, we have $pH=-(\log 2+\log(10^{-9}))$. Since $\log(10^{-9})=-9$ and $\log 2\approx0.3010$, then $pH=- (0.3010 - 9)$.
Step3: Simplify the expression.
$pH=-0.3010 + 9=8.699\approx8.7$.
Answer:
8.7