问题 选择题

国家食品监督部门检查发现市场有一种由“返青棕叶”包装的粽子,这种“返青棕叶”是硫酸铜处理过的.对此下列说法正确的(  )

A.硫酸铜中硫的化合价为+4价

B.硫酸铜溶液呈绿色

C.长期食用这种粽子会危害健康

D.棕叶上附着的硫酸铜可用醋酸除去

答案

A、铜元素显+2价,氧元素显-2价,设硫元素的化合价是x,根据在化合物中正负化合价代数和为零,可得:(+2)+x+(-2)×4=0,则x=+6;故选项说法错误.

B、硫酸铜溶液呈蓝色,故选项说法错误.

C、硫酸铜有毒,长期食用这种粽子会危害健康,故选项说法正确.

D、硫酸铜与醋酸不反应,棕叶上附着的硫酸铜不能用醋酸除去,故选项说法错误.

故选C.

完形填空

The people of Dubai have extended their reach-into the sky. In January, the world’s tallest building opened there. The skyscraper, called the Burj Khalifa, is 162 stories high, with 60-mile views from the top of the tower. At 2,717 feet, the structure stands more than 1,000 feet taller than the last tallest building, the Taipei 101 in Taiwan.

After five years of construction, the Buji Khalifa opened with a party. But now the tower is getting down to business. The skyscraper has 37 floors of office space and 1,000 apartment. It will house the world’s largest mall. The owners hope that eventually more than 12,000 people will live and work in the 6 million square feet inside the building.

The Burj Khalifa was originally named the Burj Dubai, or Dubai Tower, after the region where it was built. Dubai is a sheikdom (酋长国) which is part of the United Arab Emirates. Recently, Dubai needed a loan. Sheik Khalifa, President of the United Arab Emirates and sheik of neighboring Abu Dhabi, helped out. Burj Dubai was renamed Burj Khalifa in his honor.

The towering structure has broken a number of records besides the record for height. It has the world’s highest swimming pool, on the 123rd floor. It also has the world’s highest outdoor observation deck: Visitors can stand in the open air 124 stories above ground. Fifty-four elevators race up and down, going as fast as 40 miles an hour. Should the elevators stop working, 3,000 stairs go from top to bottom. And when it’s time to clean the windows, 36 workers will spend about three months washing them.

Reaching half a mile into the sky, the Burj Khalifa soars over even the world’s other highest skyscrapers. Its height outstrips the Taipei 101 by 60 stories. It stands more than 1,100 feet taller than China’s Shanghai World Financial Center. And Dubai’s new tower dwarfs one of the most famous skyscrapers of all: it stands more than twice as high as the Empire State Building in New York City, the world’s tallest building for more than 40 years.

小题1:How tall is the Taipei 101?  (no more than 2 words)        (2 marks)

小题2:Why was Dubai Tower changed into the Buji Khalifa?  (no more than 12 words)       (3 marks)

小题3:What’s the main idea of the fourth paragraph?         (no more than 9 words)        (2 marks)

小题4:Please give a suitable title to this passage.          (no more than 10 words)       (3 marks)

单项选择题