问题 选择题

表示下面事例的化学方程式完全正确的是[ ]

A. 田径场上发令枪响后冒出白烟:

B.利用泡沫灭火器中产生的气泡灭火:NaCO3 + HCl == NaCl + CO2↑+ H2O

C.利用一氧化碳的还原性进行高炉炼铁:

D.木炭还原氧化铜:

答案

答案:A

问答题

郑和下西洋和欧洲人开辟新航路都是世界航海史上的壮举。

据此回答:

(1)郑和下西洋最远到达哪里?新航路开辟时,航海家达·伽马到达了亚洲的哪国?

                                                                                                                                                            

(2)郑和下西洋和欧洲人开辟新航路分别产生了什么影响?

                                                                                                                                                            

                                                                                                                                                            

                                                                                                                                                            

(3)郑和下西洋体现了我国古代外交的什么传统?

                                                                                                                                                            

                                                                                                                                                            

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