A sample of rainwater with a pH of 3.5 is sure to contain a large concentration of [tex]H_3O^+[/tex]
A pH value of 7 downward is said to be acidic. Upward of 7 is said to be basic. A pH of 7 on the dot is said to be neutral.
An acid is defined as a substance that produces [tex]H_3O^+[/tex] as its only positively charged ion in solution.
Thus, rainwater with a pH of 3.5 is acidic and will contain a high concentration of [tex]H_3O^+[/tex].
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