题干

淀粉水解的产物(C6H12O6)用硝酸氧化可以制备草酸,装置如图1所示(加热、搅拌和仪器固定装置均已略去):实验过程如图1:


①将1:1的淀粉水乳液与少许硫酸(98%)加入烧杯中,水浴加热至85℃~90℃,保持30min,然后逐渐将温度降至60℃左右;

②将一定量的淀粉水解液加入三颈烧瓶中;

③控制反应液温度在55~60℃条件下,边搅拌边缓慢滴加一定量含有适量催化剂的混酸(65%HNO3与98%H2SO4的质量比为2:1.5)溶液;

④反应3h左右,冷却,减压过滤后得草酸晶体粗品,再重结晶得草酸晶体.硝酸氧化淀粉水解液过程中可发生下列反应:

C6H12O6+12HNO3→3H2C2O4+9NO2↑+3NO↑+9H2O

C6H12O6+8HNO3→6CO2+8NO↑+10H2O

3H2C2O4+2HNO3→6CO2+2NO↑+4H2O

请回答下列问题:

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    Some people choose to be vegetarian, but others are vegetarian because of their religion(宗教), their culture, or the place they live. There are vegetarians all over the world, but the country with the most vegetarians is India.
    About one billion people live in India, and most follow the Hindu religion. Hindus think it is wrong to kill animals or make them suffer. They think if they do so, they will suffer the same way one day. Hindus believe cows are sacred, and they are respected by people. Therefore, most Hindus do not eat beef.
    There are different kinds of vegetarians in the world . Some vegetarians do not eat beef or red meat, but they eat chicken and fish. Some do not eat red meat, chicken, or fish but they eat cheese, butter, eggs, milk, and other animal products. Other vegetarians do not use anything that comes from an animal. Some don t wear wool because it harms the sheep, don t use silk because it hurts silkworms, and don t eat honey because they do not want to hurt bees. Other vegetarians only eat vegetables; however they do not kill plants. For example, they will not eat carrots or potatoes because when you pick them, the plants die. They will eat apples or pears because picking them does not harm the plant. Some vegetarians do not kill or hurt any animal-not even a fly or a mosquito!
    In India, too, there are different kinds of vegetarians. Some Hindus are strict vegetarians. Other Hindus eat all meat except beef, but they only eat it about once a week. Many families eat chicken or lamb a few times a year on special occasions, like wedding. The Hindus from the upper classes do not eat meat or drink alcohol. However, the lower classes eat all meat except beef. The upper classes, or Brahmans(婆罗门), cannot kill anything that is moving. If they do, they believe they will become that animal in their next lives and will be killed, too.
    Hindus follow other rules when they eat. They rinse their mouths, arms, and legs before and after eating to clean themselves. It is a custom for the man of the house to eat thirty two mouthfuls at each meal, chewing carefully and thinking about pleasant things. Strict Hindus do not eat garlic or onions. They believe that foods have characteristics. Some foods are “hot", others are “cold” They think the strong smells of these foods are too powerful for the mild tastes and smells of other vegetables. Also, in middle class families, many women do not eat meat, but men do. Women think eating meat is something manly. They also connect meat with violence.
    Vegetarians are everywhere in both rich and poor countries. In parts of the world such as Africa, the Middle East, and Southeast Asia, meat is uncommon, and therefore it is an easy choice to be vegetarian. Surveys show that in both the United States and Britain about 4 percent of the population is vegetarian. And more and more people are choosing vegetarianism every day. Many people become vegetarian for health reasons. They look and feel better when they stop eating meat. Some famous vegetarians include Leonardo da Vince, Albert Einstein, Thomas Edison.