某氧化剂中,起氧化作用的是X2O72-离子,在溶液中0.2mol该离子恰好能使0.6mol的SO32-离子完全氧化,则X2O72-离子还原后X的化合价为
下列物质中,不属于合金的是( ) A.硬铝 B. 水银 C. 黄铜 D. 钢铁
右图中a处对应的历史时期,主要使用的能源是 ( ) A.电力 B.石油 C.煤 D.核能
根据要求,变换句子。 1.Kate is looking for her watch.(改为否定句) Kate for her watch. 2.People give me money in the bank.(改为同
--Shall I go and buy more fruit for the party? -- No, I have already bought 3 baskets. That ___ be enough. A can B ought to C may D might
We have eight managers in our company, and five of _____ are in their twenties. A. them B. whom C. who D. which
“十二五”规划纲要中“合理调整收人分配关系”首次独立成章写人。要“把蛋糕更合理地分配到群众手中”的举措是应当做到 ①提高国有资本收益
人的能卷舌和不能卷舌是由一对等位基因(R和r)控制的。某人不能卷舌,其父母都能卷舌,父母的基因型是( ) A.RR、RR B.RR、Rr