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问题 填空题

(6分)苹果酸()常用于汽水、糖果的添加剂，写出苹果酸分别与下列物质反应的化学方程式：

(1)Na                                       (2)Na2CO3                          

(3)CH3CH2OH(浓H2SO4，△)                                                     

答案

(6分) (1)略    (2)略    (3)略

单项选择题

某患者双眼被1%氨水灼伤.

其角膜损伤的严重程度主要取决于（）.

A.致伤物的酸碱性

B.与致伤物接触的时间

C.及时送医院治疗

D.抗生素防感染

E.致伤物的浓度
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单项选择题

Lloyd's, an association of London underwriters, developed from a small seventeenth century London coffee house, ______ underwriters at that time met to do business.

A．where
B．in that
C．which
D．that
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