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【单选题】
干冰和二氧化硅晶体同属 IVA 族元素的最高价氧化物,熔、沸点差别很大的原因
A.
二氧化硅的相对分子质量大于二氧化碳的相对分子质量
B.
C=O 键键能比 Si — O 键键能小
C.
干冰为分子晶体，二氧化硅为原子晶体
D.
干冰易升华，二氧化硅不能
参考答案：
参考解析：
刷刷题刷刷变学霸
举一反三
【单选题】已知同周期的X、Y、Z三种元素的最高价氧化物的水化物的酸性由强到弱的顺序是HZO4>H2YO4>H3XO4，下列判断正确的是 [ ]
A.
阴离子的还原性按X、Y、Z的顺序增强
B.
单质的氧化性按X、Y、Z的顺序减弱
C.
元素的非金属性按X、Y、Z的顺序增强
D.
气态氢化物的稳定性按X、Y、Z的顺序减弱
【单选题】Human beings have used tools for a very long time. In some parts of the world you can still find tools that people used more than two million years ago. They made these tools by hitting one stone agai...
A.
disastrous.
B.
unpredictable.
C.
exciting.
D.
colourful.
【单选题】Human beings have used tools for a very long time. In some parts of the world you can still find tools that people used more than two million years ago. They made these tools by hitting one stone agai...
A.
disastrous.
B.
unpredictable.
C.
exciting.
D.
colourful.