Which is a characteristic property of acids? a-they, turn blue litmus paper red . b-they, turn red litmus paper blue. c-they tastes bitter d-they don't react with metals

Option A

Explanation:

Option A - Blue litmus paper turns red under acidic conditions so this option is correct.

Option B - Acids do not turn red litmus paper red, bases are the ones responsible for that. Hence, this option is incorrect.

Option C - Acids generally taste sour due to the sour H+ ion; bases taste bitter due to the OH- ion. This option is incorrect.

Option D - This option is incorrect as acid reacts with metal, to form salt and hydrogen.

radioactive decay occurs in unstable atomic nuclei – that is, ones that don't have enough binding energy to hold

the nucleus together due to an excess of either protons or neutrons.