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问题 填空题

某温度时，在一个2L的密闭容器中，X、Y、Z三种物质的物质的量随时间的变化曲线，如图所示．根据图中数据，试填写下列空白：

（1）该反应的化学方程式为______

（2）反应开始至2min，气体Z的平均反应速率为______

（3）若X、Y、Z均为气体，反应达平衡时，此时容器内的压强与起始压强之比为______．

答案

（1）在反应中，X、Y的物质的量逐渐减小，Z的物质的量逐渐增大，则X、Y为反应物，Z为生成物，相同时间内物质的量的变化比值为：c（X）：c（Y）：c（Z）=（1.0-0.9）：（1.0-0.7）：0.2=1：3：2，化学反应中物质的量变化之比等于化学剂量数之比，则化学方程式为Y+3X

2Z，故答案为：Y+3X

2Z；

（2）反应开始至2min，气体Z的平均反应速率为v=

△c
△T
=
0.2mol
2L
2min
=0.05mol/（L．min），

故答案为：0.05mol/（L．min）；

（3）反应达平衡时，气体的总物质的量为：0.9mol+0.7mol+0.2mol=1.8mol，

起始时气体的总物质的量为：1.0mol+1.0mol=2.0mol，

在相同温度下，气体的物质的量之比等于压强之比，

反应达平衡时，此时容器内的压强与起始压强之比为1.8mol：2.0mol=9：10，故答案为：9：10．

单项选择题

眼电图（EOG）产生于视网膜的（）

A.神经节细胞

B.双极细胞

C.视锥细胞

D.视杆细胞

E.色素上皮
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单项选择题

Many researchers have found greater dependence and obedience in very young girls, greater autonomy and activity in boys. When a barrier is set up to separate children from their mothers, boys try to knock it down; girls cry helplessly. There is little doubt that mother’s encouragement or discouragement—of such behavior plays a major role in determining adult personality. For example, a mother often stimulates male autonomy by throwing a toy far away from her young son, thus silently suggesting to him that he leaves her to get it.
Animal studies suggest that there may be a biological factor in material behavior; mothers of some monkeys punish their male babies earlier and more often than their female offspring; they also touch their female babies more often and act more protectively toward them.
As for the controversial question of female "passivity", psychologist Helen Deutsh believes that the concept has been misunderstood. "There is no contradiction between being feminine and working. The self can be active in both men and women," she says. It is only in love and sex that passivity is particularly appropriate for women. As she sees it, passivity is no more than a king of openness and warmth; it does not mean "inactivity of emptiness".
Another controversy ranges over the effect of hormones. Aggressive women; who discount hormonal influence, disagree violently with scientific researchers, who almost unanimously agree that hormones help determine how people feel and act. So far, there have been few studies of male hormones, but scientists think they may eventually discover hormonal cycles in men that produce cyclic changes in mood and behavior. As for females, studies have indicated that 49 percent of female medical and surgical admissions, most psychiatric hospital admission and 62 percent of violent crimes among women prisoners are related with hormonal cycles in women.

What is the best title for this passage

A．Hormone Effect

B．Male and Female

C．Passivity and Activity

D．Female Passivity
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