Final answer:
The question deals with a concept in Chemistry where a solution's pH switches from 9 to 8. This indicates the solution has become 10 times more acidic. Group 12 could refer to elements in the Periodic Table but isn't directly involved.
Step-by-step explanation:
The shift from pH 9 to pH 8 mentioned in the question deals with the concept of pH in Chemistry. The pH scale is a logarithmic scale used to measure the acidity or baseness of a solution. The shift from pH 9 to pH 8 means that the solution has become 10 times more acidic.Group 12 could potentially refer to the 12th group of the Periodic Table, though it's not directly related to the concept of pH.
Learn more about pH scale