2022化学真题

<{p}>X、Y两元素的相对原子质量之比为7：2，由它们组成的某化合物中，X、Y两元素的质量比为21：8，则这种化合物的化学式为（　　）<{br/}><{/p}>

发布于 2021-02-25 23:45:10

【单选题】
A <{p}>XY<{sub}>2<{/sub}><{br/}><{/p}>
B <{p}>X<{sub}>2<{/sub}>Y<{sub}>3<{/sub}><{br/}><{/p}>
C <{p}>X<{sub}>3<{/sub}>Y<{sub}>4<{/sub}><{br/}><{/p}>
D <{p}>X<{sub}>2<{/sub}>Y<{br/}><{/p}>

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🐬旭洋 2023-02-25

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