一定温度下，在下图所示装置中，固体X与气体Y反应。生成气态产物，当改变温度时该气态产物发生逆向反应，重新生成X和Y。
利用上述反应原理和装置，对含杂质的固体Co进行提纯（杂质不参加反应），发生的化学反应为：
(固)
(气) 
(气)
(气)。下列说法正确的是[ ]
A．容器1中的温度为600℃
B．容器2中的固体是纯净的
C．该装置最终导出的气体是
和
D．固体
从容器1到容器2的过程为物理变化
答案：B
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| Last night I was driving from Harrisburg to Lewisburg, a __1__ of about eighty miles.It was late and I was in a hurry.However, if anyone asked me how fast I was __2__, I'd say I was not overspeeding.Several times I got __3__ behind a slowmoving truck on a narrow road, and I was holding my fists tightly with _4__. At one point along an open highway, I __5__ a crossroad with a traffic light.I was alone on the road by now, but as I __6__ the light, it turned red and I braked to a stop.I looked left, right and behind me. Nothing.Not a car, no suggestion of headlights, but there I sat, waiting for the light to __7__, the only human being for at least a mile in any __8__. I started __9__ why I refused to run the light.I was not afraid of being __10_, because there was obviously no policeman around, and there certainly would have been no __11__ in going through it. Much later that night, after I __12_ a group of my friends in Lewisburg and climbed into bed near midnight, the question of why I'd stopped for that light __13__ me, I think I stopped because it's part of a contract (合同) we all have with each other.It's not only the __14__, but it's an arrangement we have, and we trust each other to __15__ it: we don't go through red lights.Like most of us, I'm more likely to be __16_ from doing something bad by the social convention that __17_ it than by any law against it. It's amazing that we ever __18__ each other to do the right thing, isn't it? And we do, too.Trust is our __19__ preference. I was so __20__ of myself for stopping for the red light that night. | ||||
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