根据下图回答问题: (1)图中仪器a的名称是_______________;

题型:实验题

问题:

根据下图回答问题:  

(1)图中仪器a的名称是 _______________ ;

(2)实验室用过氧 化氢溶液和二氧化锰制取氧气时,二氧化锰起__________作用,所选用的收集装置是____或F。反应的化学方程式是____________

(3) 小张同学正在收集一瓶CO2,不知是否收集满了,其验满方法是________________。查阅资料:二氧化碳能与过氧化钠(Na2O2)反应生成碳酸钠和氧气。该反应的化学方程式是_____________。

(4)气焊和气割都需要用到乙炔。乙炔俗称电石气(化学式为C2H2),是一种无色无味具有可燃性的气体,密度比空气略小,难溶于水。实验室常用固体碳化钙与水反应制备,该反应比二氧化锰催化过氧化氢分解更加剧烈。请回答: 

乙炔的物理性质之一是____________ ;从上图选择实验室制备乙炔所用仪器的最佳组合是__________和__________(填字母)。

考点:实验室制取和收集气体的思路常用仪器的名称和选用氧气的制取和收集
题型:实验题

In many parts of the world, cars play an important role in daily life and many societies would not exist without them.  1  But this is the prediction made by a team of transport researchers who are taken seriously, not only by government but also by car manufacturers.
The Human Science and Advanced Technology Institute at Loughborough in the UK is part of an international research program.  2  That will mean much saving, no accidents and better use of roads. The super-intelligent car in the future will drive itself.  3  Instead, we will have a choice of cars and change them as frequently as we change our clothing.
According to Dr. David Davis, who leads the research team, these predictions are based on the rising cost of the car culture, which had blocked up our cities, polluted our air, and caused more deaths than both world wars put together.
Davis says, cars will be fitted with some intelligent devices(装置) to regulate(调节) the distance between one car and another.  4  computers are much safer drivers than people, so cars in a road train will be able to drive much closer together than cars driven by people.
By 2010, Dr. David Davis believes, car technology will give motorists a clear view of the road, whatever the weather conditions, by projecting an image of the road ahead on to the car’s windscreen.  5  Cars will be connected by an electronic tow bar to the car in front to form “road-trains”. “The front vehicle in such a train burns the normal amount.”says Davis. “but all the others in the train would burn about ten percent of the normal amount,  and so produce about ten percent of the pollution.”
A. The team there believes that by 2030 all cars will be computerized.
B. They believe that cars will become more important in 20 years.
C. And it will not be owned by one individual.
D. And by 2030, cars will travel in line, linked to each other electronically.
E. So the idea that in 20 years’ time, no one will own cars may be hard to believe.
F. Every driver will use less fuel in the car he owns.
G. The car will automatically speed up, or slow down, to match the speed of the car in front.
题型:实验题

广州最早最大的森林公园()

A、龙头山森林公园

B、流溪河森林公园

C、火炉山森林公园

D、大夫山森林公园

题型:实验题

下列各项中,属于条件反射的是

A.咀嚼、吞咽食物引起胃液分泌

B.异物接触眼球引起眼睑闭合

C.闻到食物香味引起唾液分泌

D.强光刺激视网膜引起瞳孔缩小

E.叩击股四头肌腱引起小腿前伸

题型:实验题

实施软件复用的目的是要使软件开发工作进行得“更快、更好、更省”。“更快”是指在市场竞争的环境中,软件产品能够及时满足市场的要求;“更好”是指开发出来的软件产品具有更好的可靠的质量;“更省”是指在开发和维护过程中成本更低。换句话说,实施软件复用的目的是快速、可靠、低成本地完成客户合同。请根据你实际参与开发的经验,论述下 * * 个问题:[问题1] 简述你参与分析和开发的系统概要和你所承担的具体工作。[问题2] 具体叙述你在软件开发过程中是如何进行软件复用的,采取过哪些软件复用的技术和措施解决过哪些相应的矛盾或问题[问题3] 简要说明你在软件开发过程中实施软件复用的具体效果。你现在认为还有哪些可以改进的地方如何加以改进

题型:实验题

当自动推力功能激活时,油门杆位于2个止动点之间,由谁来限制N1指令上限:

A、油门杆角TLA

B、N1限制

C、目标N1

D、不确定

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