(1)下列物质中,属于纯净物的是             (填写序号,

1)下列物质中,属于纯净物的是             (填写序号,下同),属于

化合物的是                

液态氧    ②蒸馏水    干冰    ④天然气    18K黄金

2)下图为某化学变化的微观模拟示意图,其中的“    ”为碳原子、“  ”为氧原子。

      请你据图回答下列问题:

+

 
 


             A           B                 C

①上图各物质中不属于化合物的是                   

②上图所示反应的化学方程式为                                       

该反应中,ABC三种物质的质量比为                        

答案

1)①、    

2)① B  

2CO + O2     2CO2   

563288(或7411

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