Final answer:
The fruit juice is acidic with a pH of 2.5.
Step-by-step explanation:
The observation that the fruit juice tastes sour and has a pH of 2.5 indicates that the juice is acidic. pH is a measure of the acidity or alkalinity of a substance, with values below 7 indicating acidity. In this case, the pH of 2.5 confirms that the juice is indeed acidic.
Learn more about Acidity of fruit juice