题干

下列叙述、对应的化学方程式、所属基本反应类型都正确的是(    )

A:用稀盐酸除铁锈    Fe2O3+6HCl=2FeCl2+3H2O               复分解反应

B:用二氧化碳制碳酸饮料   CO2+H2O=H2CO3                    化合反应

C:用铜和稀硫酸溶液反应制备铜:Cu+H2SO4=H2+CuSO4            置换反应

D:用氢氧化钠制碳酸钠   Na2CO3+Ca(OH)2=CaCO3↓+2NaOH      复分解反应

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答案(点此获取答案解析)

B

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根据短文内容,选择正确答案。

Dear Ken,

      I'm glad to hear from you. You asked me how to do well in English exams. Sometimes your knowledge is enough, but you also need good strategies.

 Here are some advice for you:

      Before you answer the questions, if you feel a little nervous, take a few deep breaths to help you relax.

      Always read the question carefully and make sure that you understand it. Read it a few times if possible.

      Find out how much each question is worth or how many points you need.

      If it asks you to give one answer, only give one.

      If there is a difficult question, don't worry. Go on with the next question and come back to it if you have time later.

      Try not to leave questions unanswered when you finish the text. Sometimes a guess may help you get points.

      When you finish, go back and check your answers. You will need to check your writing or spelling mistakes.

     Best wishes to you and your family.

                                                                                                                                                                                Yours,

                                                                                                                                                                                   Amy