Let's analyze each statement one by one.
1. Litmus green allows us to identify a base and an acid so it is correct.
2. Bases have a pH greater than 7 but for acids, their pH is lower, so 2 is not correct.
3. Strong acids and bases are able to release ions easily, this makes them conduct electricity easily. Correct.
4. Only acids will produce hydrogen gas when reacting with a metal. They will produce salt and H2. Not correct.
5. Only bases have a characteristic bitter taste. Acids have a sour taste. Not correct.
So, the properties would be possessed by BOTH acids AND bases will be: 1 and 3