Answer:
liquid
Explanation:
Adjusting pH in Water
Pure or distilled water has a pH level of 7, which means it is neutral. If you want to increase the pH of water, you must add an alkaline substance, such as baking powder, to it. If you want to decrease the pH of water, you add an acidic substance, such as lemon juice, to it
A buffer can be added to a solution to control the pH. The correct option is c.
PH is potential hydrogen. It is the value of how acidic or alkaline, the solution is.
The pH scale is consisting of 1 to 14 measure numbers, a pH less than 7 is acidic and a pH more than 7 is basic.
A buffer is a solution that maintains the pH of any solution.
Thus, the correct option is C, a buffer.
Learn more about pH
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