引起肺动脉栓塞的血栓栓子主要来自（） A.二尖瓣 B.主动脉瓣 C.三尖瓣 D.下肢

下图为实验室制取蒸馏水的装置示意图，根据图示回答下列问题

(1)图中的两处明显的错误是____________________，____________________

(2)A仪器的名称是________，B仪器的名称是________

(3)实验时A中除加入少量自来水外，还需加入少量_________________，其作用是________________。

(4)此处不用温度计行不行？简述理由。________________________________________________。

(8分)0.2mol有机物与0.5molO₂恰好完全燃烧后的产物为CO₂和H₂O(g)。产物经过浓硫酸后，浓硫酸的质量增加10.8g；再通过碱石灰剩余气体被完全吸收，碱石灰质量增加17.6g。

(1)燃烧后产物的物质的量分别为CO₂________mol、H₂O(g)__________mol。

(2)推断该有机物的分子式为_____________。

(3)若0.2mol该有机物恰好与9.2g金属钠完全反应，其核磁共振氢谱显示只有两种不同环境的H，试确定该有机物的结构简式为____________。

根据句意，用括号中所给单词的正确形式填空。

小题1:The new students had always lived with their parents before they came here. They are not used to ______ (be) away from home.

小题2:Antonio is liked by everyone because he is always ready        (help) others.

小题3:Teenagers should _______________ (allow) to go out with their friends.

小题4:We hope the weather will be fine, but it is getting even     (bad).

小题5:He believed his lucky number was 12, so he decided to live on the ___________ (twelve) floor.

小题6:Timmy has spelt the name ___________ (correct). That’s why his friend can’t find him easily.

小题7:I wonder if there are any ______________ (suggest) about how to learn English well.

革兰染色阳性时，细胞颜色应为（　　）

A．蓝紫色

B．蓝色

C．红色

D．黄色

E．无色

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