A:2H2(g)+O2(g)=2H2O(g)△H=﹣483.6kJ/mol
B:2H2(g)+O2(g)=2H2O(l)△H=﹣483.6kJ/mol
C:2H2(g)+O2(g)=2H2O(g)△H=﹣241.8kJ/mol
D:2H2(g)+O2(g)=2H2O(l)△H=﹣241.8kJ/mol
—Can you believe I paid 15 yuan for these three apples?
—You should try the supermarket________I went yesterday.Fruits there are cheap.
在相同条件下,足量的红磷在100升的空气中燃烧后,剩下气体的体积应为( )
设an是等差数列,若a2=3,a7=13,则数列an前8项的和为( ).
化学在人类生活中扮演着重要角色,下列叙述正确的是( )
下列式子成立的是( )