浓H2SO4和木炭在加热时发生反应的化学方程式是2H2SO4(浓)+CCO2↑+

题型:实验题

问题:

浓H2SO4和木炭在加热时发生反应的化学方程式是2H2SO4(浓)+CCO2↑+2H2O+2SO2↑,请从图中选用所需的仪器(可重复选用)组成一套进行该反应并检出反应产物的装置。现提供浓H2SO4、木炭和酸性 KMnO4溶液,其他固、液试剂自选。(连接和固定仪器用的玻璃管、胶管、铁夹、铁架台及加热装置等均略去)

将所选的仪器按连接顺序由上至下依次填入下表,并写出该仪器中应加试剂的名称及其作用。

考点:气体的检验
题型:实验题

已知点A(m,0)是抛物线y=x2-2x-1与x轴的一个交点,则代数式2m2-4m+2010的值是(    )。

题型:实验题

总辐射

题型:实验题

下列物质反应后一定没有Fe3+的是 [ ]

A.过量的铁丝在氯气中点燃

B.Fe( NO3)2溶液中加少量盐酸

C.过量的铁与稀硝酸反应

D.铁与氧化铁的混合物溶于盐酸中

题型:实验题

Getting your children to study can be a little like getting them to eat their vegetables.

71   Make a study time and have it at the same time every day. This will help your kids to learn to schedule their day and will give them a sense of control over how they spend their time.

Allow them to study in blocks of time, such as for half an hour with a five-minute break in the middle.    72   Ideal (理想的)study times are after dinner or right after school before dinner.

Never allow your children to study in front of the television, as that will encourage passive activity.   73

You’ll also need to help your kids find the right place to study. After you’ve set up a good study time for little learners, set up a good place where they can get those creative juices flowing.

74   Make sure there is a table or a desk and a comfortable chair.

75   This includes helping them out with their homework sometimes and being there for them with the answers to any questions. The input you give your children during study periods will help form a bond and help make studying enjoyable.

A.Pick a place where your children can study properly.

B.Hold them to the schedule they create for themselves.

C.Finally, spend time with your kids when they’re studying.

D.Keep the atmosphere light and offer lots of encouragement, too.E. Instead, use TV as a treat or a reward when the homework is completed.

F. Try to stop this bad habit by offering some sort of reward.

G. One of the best ways to form good study habits for your kids is to design a schedule that they keep to.

题型:实验题

公安机关对某娱乐场所实施检查,发现黄某利用赌博游戏机为赌博提供条件,决定对赌博游戏机实施扣押。下列做法符合《行政强制法》规定的是()。

A.1名民警和2名协警实施扣押

B.制作并当场交付扣押决定书和清单

C.办案民警拒绝听取黄某关于其抽屉里的钱是否属于赌资的申辩

D.民警回公安派出所后补作检查笔录

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