scenario: you are testing two different household solutions with your cabbage indicator, using the color key…

scenario: you are testing two different household solutions with your cabbage indicator, using the color key to the right. one solution turns blue. a possible hydrogen ion concentration for this solution is: 1×10⁻² m 5×10⁻² m 5×10⁻⁴ m 1×10⁻⁸ m done
Answer
Explanation:
Step1: Identify pH range for blue color
According to the cabbage - pH indicator color key, blue color corresponds to a pH range of 8 - 9.
Step2: Recall pH formula
The pH formula is $pH=-\log[H^+]$, where $[H^+]$ is the hydrogen - ion concentration.
Step3: Calculate hydrogen - ion concentration range for pH 8 - 9
For $pH = 8$, $8=-\log[H^+]$, then $[H^+]=1\times10^{-8}\ M$. For $pH = 9$, $9 = -\log[H^+]$, then $[H^+]=1\times10^{-9}\ M$. So the hydrogen - ion concentration for a pH of 8 - 9 is in the range of $1\times10^{-9}\ M$ to $1\times10^{-8}\ M$.
Answer:
$1\times10^{-8}\ M$