Hydrogen Peroxide jokes

Two scientists walk into a bar. The first one asks for a glass of H2O. The second one asks for a glass of H2O, too. The second one dies. Why?

Two scientists walk into a bar. The first one says: "I'll have some H2O."

The second one says: "I'll have some H2O, too." And then he died.

Two men walked into a bar, and one man asked for H20, and the other man asked for H20 too.

Only one man came out alive.