Which of the following statements about hydrogen are correct?
| 1. | Hydrogen has three isotopes of which protium is the most common |
| 2. | Hydrogen never acts as a cation in ionic salts |
| 3. | Hydrogen ion, H+, exists freely in solution |
| 4. | Dihydrogen does not act as a reducing agent |
Choose the correct option
1. (a, b)
2. (b, c)
3. (c, d)
4. (a, d)
