题干

食醋中一般含有3%﹣5%的醋酸,醋酸又叫乙酸(CH3COOH),是无色有刺激性气味的液体,能溶于水.(1)食醋可以除去水壶内的水垢,水垢的主要成分之一是碳酸钙.除水垢时,可在水壶中加入水,倒入适量醋,浸泡一段时间,碳酸钙会转变成可溶性的醋酸钙而被除掉,化学方程式为:

CaCO3+2CH3COOH═(CH3COO)2Ca+H2O+CO2↑.(2)在熬制骨头汤时,常常在汤中加入少量食醋,因为骨头中含有不溶于水的磷酸钙,当磷酸钙与醋酸作用时生成可溶于水的磷酸二氢钙,能够增加汤内的含钙量,促进人体对钙、磷的吸收和利用.(3)食醋不仅在厨房中大显身手,还是一种杀菌剂,冬天在屋子里熬醋可以杀灭细菌,对抗感冒有很大作用.(4)饮酒过量的人可以用食醋来解酒,因为乙酸能跟乙醇发生酯化反应生成乙酸乙酯(CH3COOC2H5)和水,从而达到解酒的目的.(5)醋酸能与活泼的金属发生置换反应产生氢气,家用铝盆等金属制品不能用来盛放食醋,以免被腐蚀.

根据以上内容,回答下列问题:

(a)乙酸属于____(填“有机化合物”或“无机化合物”).

(b)乙酸的物理性质____(任答一条).

(c)食醋能用来解酒的原因是____

(d)用食醋除水垢,该反应属于基本反应类型中的____反应.

(e)用铁锅炒菜时,放一点食醋能补铁的原因是____

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阅读理解

    Easter(复活节) is still a great day for worship, randy in baskets and running around the yard finding eggs, but every year it gets quite a bit worse for bunnies.

    And no, not because the kids like to pull their ears. The culprit is climate change, and some researchers found that rising temperatures arc having harmful effects on at least five species of rabbit in the US.

    Take the Lower Keys March rabbit, for instance. An endangered species that lives in the Lower Florida Keys, this species of cottontail is a great swimmer — it lives on the islands! — but it is already severely affected by development and now by rising levels. According to the Center for Biological Diversity, an ocean level rise of only 0. 6 meters will send these guys jumping to higher ground and a 0.9-meter rise would wipe out their habitat (栖息地) completely.

    The snowshoe hare, on the other hand, has a color issue. Most of these rabbits change their fur color from white in the wintertime to brown in the summer, each designed to give them better cover from predators(捕食者). As the number of days with snow decreases all across the country, however, more and more bunnies arc being left in white fur during brown dirt days of both fall and spring, making them an easier mark for predators. Researchers know that the color change is controlled by the number of hours of sunlight, but whether the rabbit will be able to adapt quick enough to survive is a big question. The National Wildlife Federation has reported that hunters have noticed their numbers are already markedly down.

    American pikas or rock rabbits, a relative of rabbits and hares, might be the firs' of these species to go extinct due to climate change. About 7-8 inches long, pikas live high in the cool, damp mountains west of the Rocky Mountains. As global temperatures rise, they would naturally migrate (迁徙) to higher ground — but they already occupy the mountaintops. They can't go any higher. The National Wildlife Federation reports that they might not be able to stand the new temperatures as their habitat beats up.

    The volcano rabbit has the same problem. These rabbits live on the slopes of volcanoes in Mexico, and recent studies have shown that the lower range of their habitat has already shifted upward about 700 meters, but there are not suitable plants for them to move higher, so they are stuck in the middle. Scientists are concerned about their populations.

    Native to the US, pygmy rabbits weigh less than 1 pound and live in the American West. They are believed to be the smallest rabbits in the world. Their habitats have been destroyed by development. Several populations, such as the Columbia Basin pygmy, almost went extinct and were saved by zoo breeding programs. Pygmy rabbits also rely on winter cover by digging tunnels through the snow to escape predators, but lesser snowfall is leaving them exposed.

All of this gives new meaning to dressing up in a giant bunny costume this Easter.