【单选题】下列说法中错误的是( )
C.
化学键的断裂和形成是化学反应中能量变化的主要原因
D.
反应物总能量和生成物总能量的相对大小决定了反应是放热还是吸热
【简答题】成语“百发百中”,只是说明射出100支箭,射中100支的命中率,不包括射出99支和101支等全部射中的情况.______.
【单选题】关于苯的下列叙述中正确的是 [ ]
B.
在苯中加入酸性KMnO 4 溶液,振荡并静置后液体变为无色
【单选题】Staying Smart: Advice on Navigating Your Career Millions of career changes occur each year. Some are natural, but many more occur in adverse circumstances. Other forces at work today further alter the...
【单选题】下列物质久置于空气中会发生相应的变化,其中发生了氧化还原反应的是( )
【单选题】In Michael Noers view, marrying a career woman is risky because
A.
career women will usually get unhappy.
B.
career women are feminists and demanding.
C.
it's more likely to lead to an unhappy marriage.
D.
the marriage is bound to be difficult.