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常温下,向10mL 0.1 mol·L-1NaOH溶液中逐滴加入0.1mol·L-1醋酸溶液,所得滴定曲线如右图所示。下列说法正确的是                                                                                          (   )

A:pH=7时,所加醋酸溶液的体积为10mL

B:pH<7时,溶液中c(CH3COO-)>c(Na+

C:7<pH<13时,溶液中c(Na+)>c(CH3COO-)>c(OH-)>c(H+

D:继续滴加0.1 mol·L-1醋酸溶液,溶液pH可以变为1

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B

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Ig Nobel Prize

    Having a meal is an easy and delightful process for most people. However, for a woodpecker (啄木鸟), it's not that simple. To get dinner, a woodpecker has to hit its head against a tree numerous times per day. Yet, amazingly, it never suffers any ill effects like brain damage. According to research, it is the woodpecker's thick head bones that protect it from the impact of the blows. For explaining that, Ivan Schwab won an Ig Nobel Prize.

    Ig Nobel Prizes are organized by The Annals of Improbable Research, an American magazine that celebrates the funny side of science. Each year, ten winners are awarded prizes in honor of their “achievements that first make people laugh, and then make them think”. Most of the award-winning research, like Schwab's, may seem unusual, but it usually grabs people's attention indeed. And no matter how ridiculous the research sounds, people can find it inspiring and amusing.

    Brian Wansink's research might interest you. He took home an Ig Nobel Prize for looking into the influence of visual factors on people's appetites. He used specially designed bowls that refilled themselves with soup while people were eating. Since these people had no idea this was happening, they just kept eating from these “bottomless bowls”. They said they didn't feel full because their bowls were not empty yet. People in this experiment ate 73 percent more soup than normal. Owing to these results, Wansink concluded that it's not people's stomachs that decide when they have eaten enough, but their eyes.

    Ig Nobel Prizes also give attention to science and technology that is a part of our daily lives. Take the karaoke machine for example. Its inventor Daisuke Inoue was employed at a nightclub, playing the piano for the customers who wanted to sing. He wasn't skillful enough to play all the songs properly. To clear up the problem, he created the karaoke machine. To Inoue's surprise, the machine caused considerable changes in entertainment worldwide. The Ig Nobel Prize was awarded to Inoue not only because his invention was entertaining, but also because it brought about “an entirely new way for people to learn to tolerate each other”.

    These research results of Ig Nobel Prizes may not be as great as Edison's light bulb or Newton's laws of motion. However, they do show people's willingness to take action and to try new ways to solve problems. According to Marc Abrahams, a founder of the Ig Nobel Prizes. “If you win one, it means that you have done something.”

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Dear Karen,

    As you probably know, it's my sister Suzie's 16th birthday in a week. We're planning a surprise party for her. Julie's going to pick her up from school as usual on Friday but she's not taking her home. She’s bringing her to the Palace Hotel, the big modern one near the station. We're having a meal there and we've also hired (租用) the ballroom (舞厅) for a party in the evening. I hope you can come!

    All her friends from school are coming and quite a few of the people from our village, too. Of course, Mum and Dad are coming up from England and I've managed to persuade (说服) our other sister, Marie, to come over from Australia. She's bringing her kids with her, too.

    After the party we're going to have another one on Saturday! Well, not really a party. We're inviting the family and close friends (that includes you) for a meal at the house. If the weather is nice, we'd like to have a barbecue in the garden. Julie's going to make a special cake for Suzie.

    Anyway, we hope to make it a really special weekend for Suzie. On Sunday we're all going for a walk in the country. You know how she loves walking and we're all going to need a bit of exercise after all that lovely food. We're hoping to go up to the lake. Marie said she wanted her kids to feed the ducks just like Suzie and she did when they were very young. I'm sure Suzie will love that too.

    It would be great if you could come over for the weekend. We would all love to see you. Let me know as soon as you can.

Best,

David