Question

200 ml of He at 0.66 atm pressure and 400 ml of
O2, at 0.52 atm pressure are mixed in a 400 ml
vessel at 25°C. The partial pressure of He and O2
will be
(1) 0.33, 0.52
(2) 0.52, 0.33
(3) 0.22, 0.45
(4) None of these​

Answer 1

0.33, 0.52

the pressure in case is reduced because V is double