问题 单项选择题

下列元素中,第一电子亲合势最大、放出能量最多的是()。

A.氮

B.氧

C.磷

D.硫

答案

参考答案:B

解析:

同周期元素中,从左到右,原子的有效核电荷增大,原子半径减小,同时由于最外电子层数逐渐增多,易与电子结合形成8电子结构,因此,元素的亲和能呈逐渐增大的趋势,至卤素达到最大值。同族元素中,从上到下,电子亲和能总的趋势是减少的。

选择题
阅读理解

Visitors to Britain may find the best place to sample local culture is in a traditional pub. But these friendly pubs can be dangerous places of potential gaffes (失礼) for the newcomers. A team of researchers have discovered some of the unknown customs of British pubs-starting with the difficulty of getting a drink. Most pubs have no waiters-you have to go to the bar to buy drinks. A group of Italian youths waiting 45 minutes before they realized they would have to fetch their own. This may sound inconvenient, but there is a hidden purpose.

Pub culture is designed to promote sociability (社交) in a society known for its reserve. Standing at the bar for service allows you to chat with others waiting to be served. The bar counter is possibly the only site in the British Isles in which friendly conversation with strangers is considered entirely suitable and really quite normal behavior. “If you haven't been to a pub, you haven't been to Britain.” This tip can be found in a booklet, Passport to the Pub: The Tourists' Guide to Pub Etiquette, a customers' rule of conduct for those wanting to sample “a central part of British life and culture”.

The trouble is that if you do not follow the local rules, the experience may fall flat. For example, if you are in a big group, it is best if only one or two people go to buy the drinks. Nothing annoys the regular customers and bar staff more than a group of strangers blocking all access to the bar while they chat and hesitate about what to order.

小题1: The underlined word “sample” in the first paragraph probably means “________”.

A.taste

B.experience

C.test

D.record .小题2:The culture of pub in Britain is so developed to ______.

A.encourage people to communicate with each other

B.encourage more people to consume drinks

C.attract more tourists to the pubs

D.form its own character of culture小题3:If you don't follow the local rules in a pub, ________.

A.you won't buy good local drinks

B.you may annoy the regular customers and bar staff

C.you may fail to feel the local culture

D.you might get into a dangerous place小题4:What may be the best title for the passage?

A.Self-service Pubs in Britain

B.British Local Pubs: Special Chat Places

C.Local Pub Culture in Britain

D.Manners in British Local Pubs