This can be very dangerous
A mixture of 3 parts concentrated sulfuric acid and 1 part 30% hydrogen peroxide solution is called piranha solution and, being both very acidic and a very powerful oxidising agent, it has a number of uses, mainly for cleaning things up to remove organic contaminants, etc.
However, it is also a very hazardous mixture and violent, spontaneous explosions have been known to occur. See for example - Piranha solution explosions.
It should only be prepared and used by professionals who are qualified to handle this mixture, and even then with great caution