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Question 2 · Single choice · 中档
我国自主研制的大型客机 C919 的机身大量使用铝锂合金材料。这是利用了铝锂合金性质 中的( )
A. 高强度、低密度 B. 高强度、导热性 C. 低密度、导电性 D. 导电性、导热性
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Question 5 · Single choice · 中档
A. 反应比较复杂 B. 产率较高 C. 副产物较多 D. 反应速率较慢
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Question 6 · Single choice · 中档
A. NH4HCO3 B. NaHCO3 C. Al(OH)3 D. CaCO3
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Question 7 · Single choice · 中档
A. 含有非极性键 B. 是直线形分子 C. 属于极性分子 D. 结构式为 $C=O=O$
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Question 8 · Single choice · 中档
A. 铁遇浓硫酸发生钝化 B. 蔗糖遇浓硫酸变黑 C. 加热时碳与浓硫酸反应 D. 加热时铜与浓硫酸反应
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Question 9 · Single choice · 中档
A. 浓缩 B. 氧化 C. 提取 D. 灼烧
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Question 10 · Single choice · 中档
A. H2S+O2→SO2 B. SO2+H2O→H2SO3 C. S+O2→SO3 D. SO3+H2O→H2SO4
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Question 11 · Single choice · 中档
侯氏制碱法中,使 NH4Cl 从母液中析出的措施不包括( )
A. 通入二氧化碳 B. 冷却 C. 通入氨气 D. 加入研
细的食盐
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Question 13 · Single choice · 中档
A. 浓氢溴酸,加热 B. NaOH/H2O,加热 C. 浓硫酸,加热 D. NaOH/C2H5OH,加热
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Question 14 · Single choice · 中档
A. 是吸热反应 B. 在常压下进行 C. 在沸腾炉中进行 D. 使用铁触媒作催化剂
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Question 15 · Single choice · 中档
A. N2 电子式为 B. N3-的最外层电子数为 6 C. N3-的质子数是 20 D. 氮原子未成对电子的电子云形状相
同
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Question 16 · Single choice · 中档
重量法测定硫酸铜晶体结晶水含量时,会引起测定值偏高的是( )
A. 未作恒重操作 B. 硫酸铜部分分解 C. 硫酸铜晶体未完全失水 D. 坩埚放 空气中冷却
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Question 17 · Single choice · 中档
铝元素之间的相互转化如图所示,下列叙述正确的是( ) 的 在
A. 实现①的转化,可通入过量CO2 B. 实现②的转化,可加入过量 NaOH 溶液 C. 实现③的转化,可加入过量 NaOH 溶液 D. 实现④的转化,可通入过量NH3
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Question 18 · Single choice · 中档
H2(g)和I2(g) 、H2(g)和I2(s)以及 HI(g)的能量高低如图所示,下列判断错误的 是( )
A. 1molH2(g)和 1molI2(g)的能量总和高于2molHI(g)的能量 B. I2(g)→I2(s)+QkJ(Q>0) C. H2(g)+I2(g)→2HI(g)+9.3kJ D. H2(g)+I2(s)→2HI(g)+53.0kJ
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Question 19 · Single choice · 中档
如图所示,具支试管内壁用水湿润后,放入铁粉、碳粉,导管插入到红墨水中。下列描 述错误的是( )
A. 具支试管底部发热 B. 负极电极反应式:$Fe-2e-=Fe2+$ C. 反应结束后,最终导管内液面下降 D. 正极电极反应式:$2H2O+O2+4e-=4OH-$
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Question 20 · Single choice · 中档
某无色溶液可能含有 H+、Na+、Al3+、Br- 、HCO3- 、SO42- 和 NO3- ,且各离子的物质 的量浓度相等。分别取样,①测得该溶液的 $pH=1$;②滴加适量氯水,溶液变为橙色;③滴
加过量 Ba(OH)2 溶液,有沉淀生成。由此可知原溶液中
A. 一定含有 NO3- B. 可能含有 Na+ C. 可能不含Al3+ D. 含有 3 种离子
二、综合分析题(60 分)
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Question 22 · Fill in the blank · 中档
高铁酸盐具有极强的氧化性,可作水处理剂。低温下,在Na2FeO4 溶液中加入 KOH 浓溶 液可析出 K2FeO4。完成下列填空: (1)写出上述得到 K2FeO4 的化学方程式_____。 (2)Na2FeO4 和稀 H2SO4 发生如下反应:Na2FeO4+H2SO4→Fe2(SO4)3+O2↑+Na2SO4+H2O。 配平上述化学方程式_____。若反应中产生 3.36L(标准状况)的氧气,则转移电子数为 _____。 (3) 实验室配制Fe2(SO4)3 溶液时,需加入少量稀硫酸,结合离子方程式用化学平衡移动原 理解释其原因______ (4)在 Fe2(SO4)3 溶液中滴加 NaHSO3 溶液,n(SO42-)增大,则还原产物是____。写出检验 。
上述反应中 Fe2(SO4)3 是否消耗完全的方法______。 (5)已知 HSO3-在水中既能水解也能电离。NaHSO3 溶液呈酸性,溶液中 $c(H2SO3)_____c(SO32-)$(选填“>”、“<”或“=”) 。
先写答案,再对照解析 等价写法不自动判错
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写好了,对答案
Answer key (1) $Na 2FeO4+2KOH=K2FeO4+2NaOH$; (2) $4Na2FeO4+10H2SO4=2Fe2(SO4)3+3O2$↑+4Na2SO4+10H2O; (3) 0.6N A; (4) Fe 3+易水解: Fe3++3H2O Fe(OH) 3+3H+,加入少量稀硫酸可使水解平衡逆向移动,抑制其水解,减 少损耗; (5) FeSO 4; (6) 取少量溶液于试管中,向试管中加入KSCN溶液,若溶液不变 红,则证明Fe2(SO4)3 消耗完全,若溶液变成红色,Fe2(SO4)3 未消耗完全; (7) <
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