500 c.c. each of hydrogen at 700 mm Hg pressure and oxygen at 600 mm Hg pressure are put together in a vessel of 1 litre capacity. The final pressure of the gas mixture will be _____________ mm Hg?

500 c.c. each of hydrogen at 700 mm Hg pressure and oxygen at 600 mm Hg pressure are put together in a vessel of 1 litre capacity. The final pressure of the gas mixture will be _____________ mm Hg?

A. 650
B. 700
C. 600
D. 375