Match Column I with Column II for the given properties/applications mentioned therein.
| Column I | Column II |
| (i) H | (a) Used in the name perhydrol |
| (ii) |
(b) Can be reduced to dihydrogen by NaH. |
| (iii) |
(c) Can be used in hydroformylation of olefin. |
| (iv) |
(d) Can be used in cutting and welding. |