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已知锌跟浓硫酸反应生成SO2,跟稀硫酸反应生成H2.使一定量的锌与100mL 16.5mol/L浓硫酸充分反应,锌完全溶解,同时收集到标准状况下的气体A 22.4L.将反应后的溶液稀释到1L,测得溶液中氢离子的浓度为0.1mol/L.
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     Many of us feel uneasy when someone stands too close to us, talks to us too loudly or makes eye contact(接触) with us for too long. But have you ever wondered why those things make you uncomfortable?
      It's all about personal peace, which means not only an imaginary space around the body, but also the space around all the senses. People feel that their space is being violated(侵犯) when they meet with an unwelcome sound, smell or look. This is probably why a man on a crowded bus shouting into his mobile phone or a woman next to you putting on strong perfume(香水) makes you feel angry.

    Whether people have had a stronger wish to protect their personal space in recent times is hard to say. Yet studies of airlines show that people have a strong desire to have space to themselves. In a survey by Trip Advisor, a travel website, people said that if they had to pay more for some extra service, they would rather have larger seats than extra food.

    Although people may need their personal space, some hardly realize it. For example, people on a bus who hold newspapers in front of their faces to read in fact keep a distance from strangers.

    Go and watch a library table. You will notice that one of the corner seats will usually be taken first, because they are the farthest way. What if someone sits opposite to you? Maybe you will pile up books as if to make a wall.

    Preference for personal space is different from culture to culture. Scientists have found that Americans generally prefer more personal space than people from other cultures. In Latin cultures, however, people are more comfortable standing close to each other.

同类题4

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    A. High tech with traditional life at Green Bank.

    Over millions of years, penguins(企鹅)have developed a keen sense of where to find food. Once they're old enough, they set off from the shores on which they were hatched for the first time and swim long distances in search of tasty fish like anchovies and sardines. But they don't search directly for the fish themselves.

    For example, when young African penguins head out to sea, they look for areas with low surface temperatures and high chlorophyll(叶绿素) because those conditions signal the presence of phytoplankton(浮游植物). And lots of phytoplankton means lots of plankton(浮游动物), which in turn means lots of their favorite fish. Well, that's what it used to mean.

    Climate change plus overfishing have made the penguin feeding grounds a mirage(海市蜃楼). The habitat is indeed plankton-rich—but now it's fish-poor. Researchers call this an “ecological trap.”

    “It's a situation where you have a signal that previously pointed an animal towards good quality habitat. That habitat's been changed, usually by human pressures. The signal stays, but the quality in the environment deteriorates.”

    Richard Sherley, a zoologist at the University of Exeter and his team used satellite imaging to track the African penguins from eight sites along southern Africa. Historically, the birds benefited from tons of fish off the coasts of Angola, Namibia and western South Africa, but now they're going hungry.

    “I was really hoping we'd see them going east, and finding areas where the fish had moved to but it ends up being quite a sad story for the penguins.” said Richard.

    The researchers calculate that by falling into this ecological trap, African penguin populations on South Africa's Western Cape have declined by around 80 percent.

    Some research groups are exploring the idea of moving chicks to a place where they can't get trapped, like the Eastern Cape. But Sherley thinks that a longer-term solution means making and carrying out rules to create more sustainable(可持续的) fishing industry, something that he says needs public support.