论文部分内容阅读
原子量:H:1 C:12 N:14 O:16Na:23 Mg:24 Al:27 P:31 S:32Cl:35.5 K:39 Fe:56 Cu:64 Zn:65Ag:108 第一部分选择 1.下列物质久置于空气中,由于发生化学反应而质量减少的是( ) (A)碳酸钠晶体 (B)四氯化碳 (C)烧碱晶体 (D)汞 2.化学符号C_2H_2和C_6H_6表明两者( ) (A)分子式相同 (B)电子式相同 (C)最简式相同 (D)结构式相同 3.氮的某种氧化物中,氮与氧的质量
Atomic weight: H: 1 C: 12 N: 14 O: 16Na: 23 Mg: 24 Al: 27 P: 31 S: 32Cl: 35.5 K: 39 Fe: 56 Cu: 64 Zn: 65Ag: 108 Part 1 Selection 1. The following Substances are left in the air for a long time and the mass is reduced due to chemical reactions () (A) Sodium carbonate crystals (B) Carbon tetrachloride (C) Caustic soda crystals (D) Mercury 2. Chemical symbols C_2H_2 and C_6H_6 indicate both () (A) The molecular formula is the same (B) The electronic formula is the same (C) The simplest formula is the same (D) The structural formula is the same 3. The quality of nitrogen and oxygen in an oxide of nitrogen