11. when the hydronium ion concentration of an aqueous solution is increased by a factor of 10, the ph value…

11. when the hydronium ion concentration of an aqueous solution is increased by a factor of 10, the ph value of the solution\na) decreases by 1 b) increases by 1\nc) decreases by 10 d) increases by 10
Answer
Explanation:
Step1: Recall pH formula
The pH of a solution is defined as $pH = -\log[H_3O^+]$, where $[H_3O^+]$ is the hydronium - ion concentration.
Step2: Let the initial hydronium - ion concentration be $[H_3O^+]_1$ and the new one be $[H_3O^+]_2$
We know that $[H_3O^+]_2 = 10[H_3O^+]_1$. The initial pH is $pH_1=-\log[H_3O^+]_1$, and the new pH is $pH_2 = -\log[H_3O^+]_2=-\log(10[H_3O^+]_1)$.
Step3: Use the logarithm property $\log(ab)=\log a+\log b$
$pH_2=-\log(10[H_3O^+]_1)=-(\log10+\log[H_3O^+]_1)$. Since $\log10 = 1$, we have $pH_2=- (1+\log[H_3O^+]_1)=-1-\log[H_3O^+]_1$.
Step4: Find the difference between $pH_1$ and $pH_2$
$pH_2 - pH_1=(-1-\log[H_3O^+]_1)-(-\log[H_3O^+]_1)=- 1$.
Answer:
A. decreases by 1