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5.除去雞蛋白膠體中混有的少量Cl-的最簡單方法是          (  )

A.加入少量硝酸銀溶液   B.加熱        C.電泳       D.滲析

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4.下列盛放物質的方法:①把汽油放在帶橡皮塞的玻璃試劑中 ②把氫氧化鈉溶液放在帶橡皮塞的試劑瓶中 ③把硝酸放在棕色的玻璃試劑瓶中  ④把氫氟酸放在無色透明的玻璃試劑瓶中 ⑤把白磷放在水中,其中正確的是  (   )

A.①②③④⑤ B.②③⑤   C.①④ D.①②③

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3.現(xiàn)有三組溶液:①汽油和氯化鈉溶液  ②39%的乙醇溶液  ⑧氯化鈉和單質溴的水溶液,分離以上各混合液的正確方法依次是                   (   )

A.分液、萃取、蒸餾   B.萃取、蒸餾、分液

C.分液、蒸餾、萃取   D.蒸餾、萃取、分液

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2.下列說法中正確的是                 (   ) 

A.非金屬氧化物一定能與堿發(fā)生反應

B.金屬氧化物一定不能與堿發(fā)生反應

C.酸性氧化物一定能與水反應生成酸

D.酸性氧化物可能與酸發(fā)生反應

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1.將下列各組物質按酸、堿、鹽順序排列,正確的是:            (   ) 

A.硫酸、純堿、石灰石          B.醋酸、酒精、醋酸鈉

C.亞硫酸、熟石灰、小蘇打        D.石炭酸、熟石灰、明礬

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13. We went through a period ___ communications were very difficult in the rural areas(上海卷).

A. which        B. whose       C. in which      D. with which

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12. They will fly to Washington, ___ they plan to stay for two or three days. (重慶卷)

A. where    B. there     C. which      D. when

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11. I’ll give you your friend’s home address,    I can be reached most evenings. (北京卷)

  A. which      B. when      C. whom      D. where

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10. Yesterday she sold her car, ______ she bought a month ago. (浙江卷)

A. whom      B. where     C. that       D. which

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9. For many cities in the world, there is no room to spread our further, _______ New York is an example. (四川卷)

  A. for which    B. in which    C. of which     D. from which

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