單項(xiàng)選擇題已知H2和He的相對(duì)分子質(zhì)量分別為2和4。2g H2與2gHe混合后體系的壓力為3300kPa,則混合氣體中He的分壓為:()
A.3300kPa
B.2200kPa
C.1100kPa
D.1650kPa
A.3300kPa
B.2200kPa
C.1100kPa
D.1650kPa