(2012•绍兴)为除去下列物质中的杂质(括号内是杂质),下列操作方法正确的是

题型:选择题

问题:

(2012•绍兴)为除去下列物质中的杂质(括号内是杂质),下列操作方法正确的是

选项物质操作方法
AFe(Fe2O3加入过量稀盐酸,充分反应后过滤
BCa0粉末(CaCO3粉末)加足量的水,充分搅拌后过滤
CNaOH溶液[Ca(OH)2溶液]通入过量CO2气体,充分反应后过滤
DCuSO4溶液(硫酸)加入过量Cu0粉末,加热,充分反应后过滤

考点:水(蒸气)的检验粗盐的提纯空气的检验物质的相互转化和制备
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公务人员不是雇员,原因是()

A.他们的服务条件,工资报酬由法律专门规定。

B.不属于雇主、雇员

C.此类人员是通过公法行为而建立起来的聘用关系

D.待遇由他们与政府协商确定

题型:选择题

推理是一种重要的研究和学习的方法,下列推理正确的是(  )

A.离子是带电的粒子,则带电的粒子一定是离子

B.氧化物中含有氧元素,则含有氧元素的化合物一定是氧化物

C.某物质燃烧生成CO2和H2O,则该物质中一定含碳、氢元素

D.燃烧一般都伴随发光和放热现象,则有发光和放热现象的变化都是燃烧

题型:选择题

How to protect children Web fans from unsuitable material on-line while encouraging them to use the Internet has long been discussed in the U.S.

For some parents, the Internet can seem like a jungle, filled with danger for their children. But jungles contain wonders as well as dangers and with good guides, some education, and a few precautions(预防措施), the wilds of the Internet can be safely navigated(航行). “Kids have to be on-line. If we tell our kids they can’t have access(机会) to the Internet, we’re cutting them off from their future,” said an expert.

Most kids have started to use search engines. Many of them are great for finding tons of interesting Internet sites, and they can also locate places where you might not want your kids to go. There are search engines designed just for kids. A certain software contains only sites that have been selected as safe. The most popular way to limit access would be to use what is known as a “content screener(过滤器)”. But this can’t be wholly reliable(可靠), and the best thing parents can do is to talk to their kids and let them know what is OK or not OK to see or do on the Internet. Another way is that mum or dad is nearby when the child is surfing(浏览) the Internet.

A few other tips

●Don’t put the PC in a child’s room but keep it in an area where mum or dad can keep an eye on things. That also makes the Internet more of a family activity.

●Ask your child what he or she has been doing and about any friends they make on-line.

●Tell your child not to give on-line strangers personal information, especially like address and phone number.

●And tell your children never to talk to anyone they meet on-line over the phone, send them anything, accept anything from them or agree to meet with them unless you go along.

小题1:The passage is mainly about the subject of _______.

A.American children going on-line

B.Internet in America

C.appreciating Internet

D.opposing children’s on-line小题2:The best way to protect children from improper material is _______.

A.to install(安装) a content screener on the computer

B.to buy some search engines for the children

C.to be nearby when they are surfing the Internet

D.to talk to the children and persuade them to tell right from wrong小题3:Which of the following is right according to the passage?

A.Surfing the Internet is the best method of educating children.

B.Children’s not having access to Internet may have effect on their progress.

C.Using a content screener is most reliable for keeping children having access to Internet.

D.Searching engines can help children to select materials fit for them.小题4:According to the passage, we can infer that _______.

A.soft wares fit for children want programming

B.a child who is on-line is in danger

C.Internet is a jungle full of danger

D.Internet contains a lot of harmful sites

题型:选择题

各省级安全生产监督管理部门、煤矿安全监察机构,以及(),应每年向国家局报送本地区本部门有关特种作业人员培训、考核、发证和复审情况的年度统计资料。

题型:选择题

因果分析图是用来寻找( )。

A.影响质量的主要原因的

B.影响质量的主要问题的

C.影响质量的主要因素的

D.解决质量问题的对策的

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