我们学习交往的第一课堂是( )
A:与老师交往
B:与同学交往
C:与家长交往
D:与朋友交往
通过以下反应均可获取H2.下列有关说法正确的是( )
①太阳光催化分解水制氢:2H2O(l)═2H2(g)+O2(g)△H1=571.6kJ•mol﹣1
②焦炭与水反应制氢:C(s)+H2O(g)═CO(g)+H2(g)△H2=131.3kJ•mol﹣1
③甲烷与水反应制氢:CH4(g)+H2O(g)═CO(g)+3H2(g)△H3=206.1kJ•mol﹣1.
Meimei is going to be an older sister. Her parents are planning to have their ________ child.
若(m﹣2)xm2-2﹣x+1=0是一元二次方程,则m的值为( )