1) Acids have a sour taste , Bases have a bitter taste.
2) Acids turn blue litmus paper into red , Bases turn red litmus paper into blue.
3) Acids react with most metals to form Hydrogen gas but only a few base react with a few metals to form Hydrogen gas
4) Both will conduct electricity. Both acids & bases are good electrolytes. Strong acids & bases conduct more electricity than that of weak acids & bases