试题与答案

今有四种粒子的结构示意图,下列说法正确的是() ①②③④ A.它们表示四种元素

题型:选择题

题目:

今有四种粒子的结构示意图,下列说法正确的是(   )

①        ②             ③        ④

A.它们表示四种元素

B.②表示的元素的原子在化学反应中易失去2个电子

C.④表示的元素是非金属元素

D.①③表示的是阳离子

答案:

答案:B

题目分析:元素是具有相同核电荷数或质子数的同一类原子的总称,故质子数相同的原子或离子属于同一种元素,②④的质子数相同,属同种元素,A错误;当原子的最外层电子数小于4时,易失电子,②表示的元素的原子最外层电子数为2,易失去2个电子,B正确;12号是镁元素,属金属元素,C错误;质子数等于核外电子数时为原子,质子数不等于核外电子数时为离子,①表示的是阴离子③ [表示的是阳离子,D错误。故选B。

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题型:阅读理解

When first entered ,Vanak Restaurant does not look like much of a restaurant, but once the pleasant smells of kabob(烤羊肉串)hit the senses ,you are incapable of calling it anything less.

Owned by a local couple, this Persian restaurant has an inviting, homelike atmosphere that many restaurants lack.

The space is small with only a few dining tables and nearly no decoration, but the environment is truly charming.

Lying in a hardly noticeable street corner, the restaurant still attracts all customers, especially those experienced in the delights of Middle Eastern cooking.

A common sight is that of old Persian men sitting in the corner talking loudly about world topics, watching news events on TV, drinking a black tea known as Persian chai, and reading local Persian newspapers all the while trying to finish off their plate piled with food.

The variety of food at the restaurant is limited, but the amount of each dish is fairly large. Most of the meals can serve two people and are under $10,so not only is it affordable but practical as well.

The food, especially appeals to health-conscious eaters because each dish is very healthy, made with limited fat and oil and served straight off the grill(烤肉架).

The main dish that the restaurant is popular for is its kabobs, which are different style of grilled meat.

One delicious and extremely healthy dish is the Joojeh Kabob, which is made of grilled chicken pieces served with either rice or bread. Another great kabob is the Chelo Kabob, kabob consisting of grilled beef.

Although the restaurant is small, the atmosphere and the food is delicious. It is a place that should not be overlooked.

小题1:When first entering the restaurant, one can find that it      

A.is splendidly decorated

B.has pleasant smells of kabobs

C.is crowded with dining tables

D.looks like a common restaurant小题2:What activity is also mentioned apart from dining in the restaurant?

A.Watching news events on TV

B.Drinking a kind of black coffee

C.Reading local English newspapers

D.Discussing world topics in low voices小题3:The food of the restaurant         

A.is served in small amounts

B.is rather expensive

C.is rich in variety

D.is very health小题4:It can be inferred from the passage that the restaurant            .

A.occupies a large space

B.owns a favorable location

C.is popular for its special food

D.has a quiet environment inside

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