化学是一门以实验为基础的自然科学．下列实验操作或实验所得出的结论正确的是（ ）
A．在过滤和蒸发的实验操作中，玻璃棒的作用相同
B．在实验室制取蒸馏水的装置中冷却水应上进下出
C．分液时，分液漏斗中下层液体从下口放出，上层液体从上口倒出
D．某无色溶液中加入盐酸产生无色无味且能使澄清石灰水变浑浊的气体，则该溶液中一定含有大量的CO32-
A．过滤中玻璃棒的作用是引流；蒸发中玻璃棒的作用是搅拌防止液体飞溅，故A错误；
B．冷凝器的水应下进上出，这时冷凝效果最好，故B错误；
C．分液操作时，分液漏斗中下层液体从下口放出，上层液体从上口倒出，避免两种液体相互污染，故C正确；
D．HCO3-也能与酸反应生成无色无味且能使澄清石灰水变浑浊的气体，则不一定含有CO32-，故D错误．
故选C．
认真阅读下面短文，并在表格内的空白处填上一个合适的单词，注意：每空一词。 The average human experiences a lot of dreams while they sleep at night. But what exactly do they mean? The following explanations deal with four most common dreams and some of the possible meanings behind them, according to experts. Please note that, while certainly interesting, dream analysis is a highly subjective(主观的) field of study. Dreams about being chased (追逐) Dreaming about being chased generally means you may be avoiding a person or something painful, annoying or fearful. It could be a reminder that trying to avoid the problem could lead to more such dreams. Most people dream about being chased at one point or another. It’s both common and natural. Dreams about death According to Jeffrey Sumber, a psychotherapist (精神治疗师) and author, dreams about death often indicate “the ending of something, whether that’s a job or a relationship”. He suggests a dream about death can also indicate attempts to remove anxiety or anger. These dreams don’t suggest a person will actually die, he explains. There are no tricks when it comes to avoiding such dreams. The only way is to do our inner work and make peace with it. People who have dreams about death tend to be those who are entering an uncertain period in their life. It could be a life-changing event that creates anxiety and fear of the unknown. Dreams about falling Dreaming about falling can have a physiological basis, according to Cathleen O’ Connor, Ph. D. As the body goes deep into sleep and the nervous system begins to be quiet, blood pressure and heart rate drop and this change can cause a falling dream. O’Connor says that dreaming about falling is the mind’s way of warning the dreamer of a situation in his or her waking life where they feel out of control. “If dreams of falling bring feelings of fear, you should realize that the goal is not to avoid them but rather to work with those dreams in your waking state and deal with the fear so you can regain your balance,” O’ Connor says. Dreams about celebrities (名人) “Celebrities carry some kind of message that’s associated with personal achievements or lack,” says Shelley Smith, founding director of the Yoga Health & Therapy Center. “A person dreaming about a celebrity is looking for inspiration … or some characteristic that is associated with that celebrity. “That’s one of the features of dream images, and they are not under our control,” Smith says. “Your experience while you’re sleeping is coming from a place that’s totally unconscious (无意识的).” “There is no one group that we can say has this particular dream more than another,” she says, “The image is energetic and specific to what the person’s need is. For example, accomplishment, health, and rising to the top --- whatever is associated with that celebrity.
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