问题 选择题

根据你的生活经验和所学的化学知识,判断下列做法或说法正确的是(  )

①用钢丝球洗刷铝制炊具              ②用食盐水去除铁钉表面的铁锈

③将活性炭放入硬水中使其软化        ④用燃着的火柴检查液化气罐是否泄漏

⑤用地沟油烹饪食物会危害人体健康    ⑥在煤炉上放一盆水可防止煤气中毒.

A.①②⑤

B.③④⑤

C.①③⑤⑥

D.只有⑤

答案

①铝锅表面有一层致密的氧化物薄膜,对铝锅起到保护作用.如果用钢丝球擦洗,可能把氧化物薄膜擦去,所以不能用钢丝球洗刷铝制炊具;

②铁锈的成分是氧化铁,氧化铁和氯化钠不能反应,故用食盐水不能去除铁钉表面的铁锈;

③活性炭具有吸附性,能够净化水,但是不能使硬水软化;

④液化气属于易燃物,用燃着的火柴检查液化气罐是否泄漏容易造成火灾的产生,甚至爆炸;

⑤地沟油中含有多种对人体有害的物质,所以用地沟油烹饪食物会危害人体健康;

⑥一氧化碳难溶于水且不会和水反应,因此在煤炉上放一盆水不能防止煤气中毒.

故选D

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阅读理解

Nickname (昵称): Hawaii’s Island of Adventure.

Size: 4,028 square miles.

Population: 148,677. The most heavily populated areas are Hilo on the east side and     Kailua-Kona on the west.

Temperature: Averages between 71℉ and 77 ℉ year around —expect the mercury ( 水银柱) to drop at higher Heights.

Beaches: 47  Golf Courts: 20   Highest Peak: Mauna Kea, 13,796 feet.

Agriculture: The bulk (主体) of Hawaii’s farming products are grown and processed on the Big

Island, including coffee, macadamia nuts and papaya.

Lodging: 9,655 rooms in total; nightly rates range from $ 35 to $ 5,000.

Airports: Hilo International Airport on the east side and Kona International Airport on the west

side.

Rental Cars: All of the nationally known rental car companies have locations at Hilo  International and Kona International Airports as well as many resorts. In addition, Hilo, Kona and the major resort areas are serviced by taxis.

Resources: Call (800) 648-2441 to order a video, a poster, brochures and maps from the Big Island Visitors Bureau. Turn to www. Bigisland. org for updated information.

Shopping: The largest shopping centers are in Hilo, Kona, Waimea and the Kona Coast.

小题1:_____ are mostly interested in reading the passage.

A.Tourists

B.Students

C.Businessmen

D.Officials小题2:The average population per square mile on the island is about _____.

A.28

B.37

C.32

D.44小题3:The underlined part “expect the mercury to drop at higher heights” means _____.

A.Things are easy to lose weight at higher places

B.Dropping things from higher places is expected

C.Temperature is expected to be lower at higher places

D.Temperature is expected to be higher at higher places