25℃时,将体积为Va、pH = a的某一元强酸溶液与体积为Vb、pH = b的

题型:选择题

问题:

25℃时,将体积为Va、pH = a的某一元强酸溶液与体积为Vb、pH = b的某二元强碱溶液充分混合后,溶液的pH = 7,已知b = 6aVa < Vb,下列有关b的说法正确的是

A.b可能等于12

B.b可能等于13

C.b一定小于12

D.b一定大于12

考点:燃烧热水的离子积常数水电离的影响因素水的电离平衡
题型:选择题

阅读理解。

     One day, Bob took two of his friends into the mountains. They put up their tents (帐篷) and then rode

off to a forest to see the trees growing.

     In the afternoon, when they were about ten kilometers from their camp (营地), it started to snow. More

and more snow fell. Soon Bob could hardly see his hands before his face. He could not find the road. Bob

knew there were two roads. One road went to the camp, and the other went to his house.But all was white

snow. Everything was the same. How could he take his friends back to the camp?

     Bob had an idea. The horses! Let the horses take them back! But what would happen if the horses took

the road to his house? That would be a trip of thirty-five kilometers in such cold weather!

     It was getting late. They rode on and on. At last the horses stopped. Where were they? None of them

could tell. Bob looked around. What was that under the tree? It was one of their tents!

1. Bob and his two friends went to the forest to _____. [ ]

A. build their camp

B. find their way home

C. enjoy the mountains in the snow

D. watch the trees in the forest 

2. They could not find their way back because _____. [ ]

A. there was only one road to their camp

B. they couldn't decide which of the two roads led to their tents

C. there were no roads in the mountains at all

D. everything was covered by the white snow

3. It is clear that they wanted the horses to take them to _____. [ ]

A. John's house

B. the camp

C. the forest

D. the mountains

4. The horses stopped because _____. [ ]

A. it was getting late

B. they were tired after running for a long way

C. they knew that they had got to the camp

D. they had seen John's house

题型:选择题

腹内实质性脏器病变,宜先选用的检查是()

A.透视

B.摄片

C.B超

D.CT

E.脑血管造影

题型:选择题

下图中所反映的现象能够出现的原因是

19 世纪晚期英国海外贸易示意图

① 工业革命的完成 ② 殖民帝国的确立 ③ 交通运输工具的先进 ④ 拥有“世界工厂”的优势 [ ]

A.①②③

B.①③④

C.②③④

D.①②③④

题型:选择题

(3分)现有下列物质:维生素A、维生素C、维生素D;碘元素、铁元素、锌元素;糖类、淀粉、油脂。请选择正确答案填在相应的空格里。

(1)人体缺乏某种维生素会引起干眼症、夜盲症,这种维生素是__________

(2)人体摄入某种微量元素过量,可能引发甲状腺机能亢进,这种微量元素是____

(3)既能为人体提供热量,又能提供必需脂肪酸的物质是__________

题型:选择题

二十岁的男性患者,因兴奋话多与少语少动交替发作10月余入院。患者在10个月前无明显诱因第一次出现兴奋话多,讲话滔滔不绝,不让他做的事情偏要做,别人阻止他时,他却说在做好事,自己在纸上写了数字就变成了支票,可以拿去给别人治病,在当地医院住院治疗后好转,尚能坚持工作,在出院后的2个月,因与女友吵架后出现不愿说话,不愿上班,家人反映变懒了,在当地医院给予米帕明治疗半个月后恢复正常。住院前半个月,患者变得话多,易激惹,容易发脾气,讲自己能当公司总裁,工作能力强,将来可以组建一个跨国公司。

此患者最合适的治疗方案()

A.心境稳定剂

B.心境稳定剂和第二代抗精神病药

C.第二代抗精神病药

D.心境稳定剂和第一代抗精神病药

E.第一代抗精神病药

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