Which of the following can be acidic (acid) and basic (base)?

Question

calamansi, tomato, banana, water, milk, vinegar, softdrink, aspirin, milk of magnesia.

Answer 1

all are acidic except water, which is neutral and milk of magnesia which is basic

Answer 2

Calamansi I haven't heard of.  Milk of magnesia is basic, water is neutral (or nearly so), and the rest are acidic.

Answer 3

to know the acidic and basic nature  experimentally use indicator solution or litmus solution

Acids turn red litmus blue while bases turn vice versa

Answer 4

Water can act as either a weak acid or as a weak base.