2.點解BaSO4可以可H2SO4 react ,但唔可以同HCl同HNO3 react?
3.係一個密封ge flask入面,係唔係愈多gas,個pressure愈大?
更新1:
SORRY , 應該係點解BaCl2可以可H2SO4 react ,但唔可以同HCl同HNO3 react?