问题 选择题

下列物质中属于混合物的是(  )

A.氯酸钾加热完全反应后所得的固体

B.过氧化氢溶液加热完全反应所得的液体

C.净化后的空气

D.冰水混合物完全融化后的液体

答案

A、氯酸钾受热分解能生成氯化钾和氧气,完全反应后所得的固体是氯化钾,属于纯净物;

B、过氧化氢溶液受热分解能生成水和氧气,加热完全反应所得的液体是水,属于纯净物;

C、净化后的空气中含有氮气、氧气、二氧化碳、稀有气体等物质,属于混合物;

D、冰和水是同种物质,只是状态不同,冰水混合物完全融化后的液体是水,属于纯净物.

故选:C.

阅读理解

Everyone’s at it, even my neighbors. I thought I might be the only person left in the world who hadn’t done an eBay deal. So, I decided to try my hand at online auction(网上拍卖).

Buying for Beginners

Sign up on www. eBay. co. uk. Most items (e.g. tables, computers and books) ready for auction will come with a picture and a short description; others may be marked with “Buy It Now” and have a fixed price. You can buy these right away.

If the item is being auctioned, you offer the highest price you are prepared to pay and eBay bids (出价) for you. The bid will be increased little by little until it goes beyond your highest bid, then you are emailed and asked if you would like to bid again. Auctions last up to 10 days and when they finish, you get an email telling you whether you have won the item.

How to Pay

Sellers decide how they would like to be paid and you need to check this before placing a bid as you might not want to post a check or postal orders. The easiest way is through PayPal, an online payment system that takes the money away from your credit card.

Selling Made Simple

If you plan to sell on eBay, it helps to include a picture of the item. I followed my friends’ advice and put up the items I wanted to sell for a 10-day auction, starting on a Thursday. This way buyers had two weekends to bid.

The big Things in Life

It’s easy to post a small item, but furniture is a big part of eBay and this has to be collectively sent by deliverymen. Check the ways of delivery before you bid.

小题1:What is the passage mainly about?

A.How to make payment online.

B.Ways of making delivery online.

C.Advantages of an online auction system.

D.How to use an online-auction system.小题2:After bidding for an item, a buyer ________.

A.has chances to make higher bids

B.will get what he wants in ten days

C.should make payment immediately

D.may check its picture and description小题3:The easiest way of making payment mentioned in the passage is ________.

A.through a local banking system

B.by sending the money to the seller

C.by paying the deliveryman directly

D.through an online payment system

问答题