把场景中的图形转换成元件指令的快捷键是()
A.Shift+F7
B.F8
C.Alt+F5
D.Ctrl+F8
参考答案:B
63. He was elected_______of the football team last year.
A.a captain
B.the captain
C.captain
D.Captains
已知1 g氢气完全燃烧生成水蒸气时放出热量121 kJ,且氧气中1 mol O=O键完全断 裂时吸收热量496 kJ,氢气中1 mol H―H键断裂时吸收热量为436 kJ,求水蒸气中1 mol H―O键形成时放出热量
A.463kJ
B.557 kJ
C. 486kJ
D.188 kJ