问题 选择题

下列各组物质,按混合物、化合物、单质顺序排列的是(  )

A.冰水共存物、二氧化硫、氮气

B.石油、煤、天然气

C.洁净的空气、五氧化二磷、液态氧

D.生石灰、酒精、水银

答案

答案:C

题目分析:由两种或两种以上的物质混合而成的物质是混合物;由同种元素组成的纯净物是单质;由不同种元素组成的纯净物是化合物;根据以上概念进行分析判断。A、冰是水的固态形式,是由不同种元素组成的纯净物,属于化合物;干冰是由不同种元素组成的纯净物,属于化合物;氮气是由一种元素组成的纯净物,属于单质; B、石油、煤均是由多种物质混合而成的,均属于混合物;天然气的主要成分是甲烷,含有气体杂质,属于混合物;C、洁净的空气中含有氮气、氧气、二氧化碳等多种物质,属于混合物;五氧化二磷是由氧元素和磷元素两种元素组成的纯净物,属于化合物;液态氧是由一种元素组成的纯净物,属于单质;符合混合物、化合物、单质顺序排列.故是正确答案选C。D、生石灰属于化合物,酒精是由不同种元素组成的纯净物,属于化合物,水银是由一种元素汞组成的纯净物,属于金属单质;故选C

阅读理解

Ireland has had a very difficult history. The problems started in the 16th century when English ruler tried to conquer Ireland. For hundreds of years, the Irish people fought against the English, Finally, in 1921, the British government was forced to give independence to the south of Ireland. The result is that today there are two "Irelands". Northern Ireland, in the north, is part of the United Kingdom. The Republic of Ireland, in the south, is an independent country.

In the 1840s the main crop, potatoes, was affected by disease and about 750,000 people died of hunger. This, and a shortage (短缺) of work, forced many people to leave Ireland and live in the USA, the UK, Australia and Canada. As a result of these problems, the population fell from 8.2 million in 1841 to 6.6 million in 1851.

For many years, the majority of Irish people earned their living as farmers. Today, many people will work on the land but more and more people are moving to the cities to work in factories and offices. Life in the cities is very different from life in the countryside, where things move at a quieter and slower pace.

The Irish are famous for being warm-hearted and friendly. Oscar Wilde, a famous Irish writer, once said that the Irish were "the greatest talkers since the Creeks". Since independence, Ireland has revived (复兴) its own culture of music, language, literature and singing. Different areas have different styles of old Irish songs which are sung without instruments. Other kinds of Irish music use many different instruments such as the violin, whistles, etc.

小题1:What does the author tell us in paragraph 1?

A.How the Irish fought against the English.

B.How Ireland gained independence.

C.How English rulers tried to conquer Ireland.

D.How two “Irelands” came into being.小题2:We learn from the text that in Ireland________.

A.food shortages in the 1840s led to a decline in population

B.people are moving to the cities for lack of work in the countryside

C.it is harder to make a living as a farmer than as a factory worker

D.different kinds of old Irish songs are all sung with instruments小题3:The last paragraph is mainly about________.

A.the Irish character

B.Irish culture

C.Irish musical instruments

D.a famous Irish writer小题4:What can be the best title for the text?

A.Life in Ireland

B.A very difficult history

C.Ireland, past and present

D.the independence of Ireland

单项选择题