根据以下装置图,回答下列问题: (1)双氧水(H2O2)是一种无色液体,国外化

题型:实验题

问题:

根据以下装置图,回答下列问题:

(1)双氧水(H2O2)是一种无色液体,国外化学实验室用它来制取氧气,用此方法制取氧气时应选用的气体发生装置是___________;收集装置是____________。

(2)化学实验室用氯化铵和熟石灰这两种固体混合加热来制取氨气,氨气的密度比空气小,且易溶于水;则制取氨气时,应选用的气体发生装置是_____________;收集装置是______________。

(3)将两装满氧气的集气瓶,按下图所示,用带火星的木条分别用A、B两种方式迅速插入,观察到木条复燃,且在A中燃烧比在B中燃烧更旺。以上实验现象表达了氧气的性质有:①________________________________; ②______________________________。

考点:氧气的制取和收集实验室制取和收集气体的思路
题型:实验题

不直接参与细胞免疫的细胞()

A.巨噬细胞

B.Th1细胞

C.Th2细胞

D.CTL

E.靶细胞

题型:实验题

写出下列反应的化学方程式.

(1)实验室用双氧水制取氧气:______.

(2)用天然气作燃料:______.

(3)碳酸钠溶液与石灰水反应:______.

题型:实验题

近几年来,我国逐步加大了对农业和农村的投入;加大了对少数民族地区在经济发展方面的投入;加大了对贫困地区的投入;各地逐年提高最低工资标准……这充分体现了我 国在经济发展方面

A.已经建设成为了富强、民主、文明、和谐的现代化国家

B.是人民当家作主的国家

C.致力于实现全体人民的共同富裕

D.人民群众平等享有各项权利[

题型:实验题

强直性脊柱炎的X线表现特点()。

A.常蔓延数个椎体,晚期增生明显.骨性融合成块

B.常累及多数椎骨,多同时伴有双骶髂关节病变。晚期韧带钙化呈"竹节样",椎体无破坏

C.累及单个椎体,椎间隙正常,常有椎弓根破坏

D.椎体破坏,可有死骨,椎体压缩呈楔形,椎间隙变窄

E.骨质增生及间隙变窄,椎体边缘硬化,无骨质破坏

题型:实验题

Automotive accidents are one of the leading causes of death in children. Child safety advocates argue that harsh penalties should be imposed on drivers who fail to place children under 30 pounds in rear-facing children’s seats in the rear of the car whenever a car is in motion. Such penalties, they argue, will help save children’s lives.All of the following statements support the argument of the child safety advocates EXCEPT:()

A. The rear seats of a car are safer for all passengers, both adults and children, in the event of an accident.

B. Studies have shown that children in rear-facing seats have been shown to sustain less serious injuries in accidents than children in front-facing seats.

C. Studies have shown that children under 30 pounds can sustain serious injuries in even minor accidents if they are not properly restrained.

D. Studies have shown that children between 60 and 90 pounds are safest in a car when using both a seat belt and a properly sized booster seat.

E. Some drivers will not abide by regulations unless they are forced to do so by the threat of harsh penalties.

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