容器编号
起始时各物质物质的量/mol
平衡时反应中的能量变化
N2
H2
NH3
①
1
3
0
放出热量a kJ
②
2
放出热量b kJ
③
6
放出热量c kJ
下列叙述正确的是( )
A:放出热量关系:a<b<92.4
B:三个容器内反应的平衡常数:③>①>②
C:达平衡时氨气的体积分数:①>③
D:N2的转化率:②>①>③
用特殊疑问词或短语填空
(1)—____ do children of migrants(流动人员子女) go to school?
—By school bus or walk.
(2)— ____ does it take you to get home from work every day?
—About twenty minutes.
(3)—____ is it from your uncle's home to your grandma's?
—It's about three kilometers.
(4)—____ is twenty and fifty?
—It's seventy
(5)—I walk to school. ____ about you, Jane?
—I ride my bike.
我国大力发展火力发电,火电站进的是煤,出的是电,在这个过程中能量的转化是( )
Debbie is growing fast. She is even than her mother .
如图所示,半径R=0.9m的光滑的半圆轨道固定在竖直平面内,直径AC竖直,下端A与光滑的水平轨道相切.一个质量m=1kg的小球沿水平轨道从A端以VA=3 5 m/s的速度进入竖直圆轨道,后小球恰好能通过最高点C.不计空气阻力,g取10m/s2.求: