Final answer:
The pH of apple juice with a hydronium ion concentration of 1.6x10^-4 m is calculated using the formula pH = -log[H3O+], which results in a pH of approximately 3.80, indicating that apple juice is acidic.
Step-by-step explanation:
To calculate the pH of a solution when the hydronium ion concentration is known, you can use the formula pH = -log[H3O+]. For apple juice with a hydronium ion concentration of 1.6x10−4 m:
pH = -log(1.6x10−4)
To find the pH, simply plug the hydronium ion concentration into the formula like so:
pH = -log(1.6x10−4) ≈ 3.80
The pH value indicates that apple juice is acidic, because any pH value below 7 is considered acidic. The pH scale typically ranges from 0 to 14, with 7 being neutral. Values below 7 indicate acidity and values above 7 indicate alkalinity.