问题 选择题

下列有关物质的检验或区分方法中不正确的是(  )

A.向某溶液中加入稀盐酸,有无色气体放出,则证明该物质是碳酸钠

B.鉴别氧气和空气两瓶气体时,将燃着的木条分别插入瓶中,燃烧更旺的为氧气

C.某化肥与碱共热,若产生使湿润红色石蕊试纸变蓝的气体,证明为铵态氮肥

D.向某溶液中加入稀盐酸后无变化,再加入BaCl2溶液生成白色沉淀,证明溶液中含SO42-

答案

A、向某溶液中加入稀盐酸,有无色气体放出,不能证明该物质是碳酸钠,因为锌、镁、铝、铁等金属能和稀盐酸反应生成无色气体氢气.不正确.

B、将燃着的木条分别插入瓶中,燃烧更旺的为氧气,无明显变化的是空气.正确.

C、某化肥与碱共热,若产生使湿润红色石蕊试纸变蓝的气体,说明该气体是氨气,进一步可以证明为铵态氮肥.正确.

D、向某溶液中加入稀盐酸后无变化,说明溶液中不含有银离子,再加入BaCl2溶液生成白色沉淀,该沉淀是硫酸钡,进一步可以证明溶液中含硫酸根离子.正确.

故选:A.

填空题
阅读理解

In today’s world, so many people like traveling around the world. Traveling abroad can be expensive, but there are some ways of visiting Britain cheaply. So we hope  we can give you some good ideas.

If you don’t go there in the busy months—July and August, your visit may be cheaper. There will be fewer visitors. The weather in Britain can be pleasant from April to the end of September. Of course  you can go there in winter, but it is often dark by 4 pm. Many places, such as large houses and castles(城堡)are closed in winter. However, if you are interested in museums, art galleries(画廊) or theaters, winter may be the good time to visit.

If you are a student, it is a good idea to apply for (申请) an International Student Identify Card. With the card, you can save a lot of money. You can get the card from your local (当地的)student travel office, and you can also call (44)08708 413224 to get it. To get the card, you need to show that you are a student, get a passport photo, and pay for a little money.

小题1:If you want to visit ____, it is not the good time to visit Britain in winter.

A.museums

B.castles

C.art galleries

D.some places小题2: Which of the following is not true?

A.There are many visitors in July in Britain.

B.Days are very long in winter in Britain.

C.Many museums are not closed in winter.

D.Only student can get the International Student Identify Card.小题3: A student without an International Student Identify Card may______.

A.get a little money.

B.watch TV at home.

C.spend more money.

D.save a lot of money.小题4: Which of the following is the best title?

A.How to have a cheaper trip in Britain.

B.How to travel to Britain.

C.When to travel to Britain.

D.Why to travel to Britain.