离子不共存

发生复分解反应并生成微溶或难溶物

溶于一般酸(如稀盐酸、稀硫酸、醋酸等)的沉淀:

\[\quad \ce{BaCO3}, \ce{CaCO3}, \ce{Ag2CO3}, \ce{FeS}, \ce{ZnS}, \ce{MnS}, \ce{Fe(OH)2} \]

溶于硝酸(但不溶于一般非氧化性酸)的沉淀:

\[\quad \ce{Ag2S}, \ce{CuS} \]

不溶于酸(既不溶于一般酸,也不溶于硝酸)的沉淀:

\[\quad \ce{BaSO4}, \ce{PbSO4}, \ce{AgCl}, \ce{AgBr}, \ce{AgI}, \ce{HgS}, \ce{KFe[Fe(CN)6]} \]

生成弱电解质

生成弱电解质的物质不能大量共存

与氢离子反应

\[\ce{OH- + H+ -> H2O} \]

\[\ce{SO3^2- + 2H+ -> H2O + SO2 ^} \]

生成了气体和水,若仅生成亚硫酸氢根,可以暂时共存

\[\ce{HSO3^- + H+ -> H2O + SO2 ^} \]

\[\ce{S^2- + 2H+ -> H2S ^} \]

同理,如果是硫氢根的话,可以共存,也不算做生成弱电解质

\[\ce{HS^- + H+ -> H2S ^} \]

\[\ce{CO3^2- + 2H+ -> H2O + CO2 ^} \]

\[\ce{HCO3^- + H+ -> H2O + CO2 ^} \]

\[\ce{CH3COO^- + H+ -> CH3COOH} \]

\[\ce{SiO3^2- + 2H+ -> H2SiO3 v} \]

\[\ce{ClO^- + H+ -> HClO} \]

\[\ce{F^- + H+ -> HF} \]

\[\ce{PO4^3- + 3H+ -> H3PO4} \]

\[\ce{HPO4^2- + 2H+ -> H3PO4} \]

\[\ce{H2PO4^- + H+ -> H3PO4} \]

\[\ce{C6H5O^- + H+ -> C6H5OH} \]

苯酚是极弱的电解质

\[\ce{C2O4^2- + 2H+ -> H2C2O4} \]

\[\ce{Al(OH)4^- + H+ -> Al(OH)3 v + H2O} \]

\[\ce{Al(OH)4^- + 4H+ -> Al^3+ + 4H2O} \]

与氢氧根反应

\[\ce{H+ + OH- -> H2O} \]

\[\ce{NH4+ + OH- -> NH3\cdot H2O} \]

氨水不加热挥发的速率一般

\[\ce{Mg^2+ + 2OH- -> Mg(OH)2 v} \]

\[\ce{Cu^2+ + 2OH^- -> Cu(OH)2 v} \]

\[\ce{Zn^2+ + 2OH^- -> Zn(OH)2 v} \]

\[\ce{Fe^2+ + 2OH^- -> Fe(OH)2 v} \]

\[\ce{Fe^3+ + 3OH^- -> Fe(OH)3 v} \]

\[\ce{2Ag+ + 2OH^- -> Ag2O v + H2O} \]

\[\ce{Al^3+ + 3OH^- -> Al(OH)3 v} \]

\[\ce{Al(OH)3 + OH^- -> [Al(OH)4]^-} \]

\[\ce{Ca^2+ + 2OH^- -> Ca(OH)2 v} \]

\[\ce{HCO3^- + OH^- -> CO3^2- + H2O} \]

\[\ce{HSO3^- + OH^- -> SO3^2- + H2O} \]

本质酸碱中和

\[\ce{HPO4^2- + OH^- -> PO4^3- + H2O} \]

这里是酸碱中和,如果和\(\ce{H+}\)反应,也是酸碱中和,但磷酸根充当的身份可能发生变化

\[\ce{H2PO4^- + OH^- -> HPO4^2- + H2O} \]

\[\ce{HS^- + OH^- -> S^2- + H2O} \]

总结

多元弱酸分步电离,到中间某个阶段的离子,加碱进一步电离,加酸则回退`

如果没有水解的酸容易分解,如碳酸,那么这个分解的过程和电离与水解均无关,而是一步到位的分解反应,反之,分解出的气体溶于水生成酸同理

出气体

\[\ce{NH4+ + OH^- ->[\Delta] NH3 ^ + H2O} \]

\[\ce{CO3^2- + 2H+ -> H2O + CO2 ^} \]

\[\ce{SO3^2- + 2H+ -> H2O + SO2 ^} \]

\[\ce{HS^- + H+ -> H2S ^} \]

复分解反应杂项

\[\ce{[Al(OH)4]^- + HCO3^- -> Al(OH)3 v + CO3^2- + H2O} \]

强酸制取弱酸

氧化还原反应

经典氧化还原

氧化剂 \ 还原剂 \(\ce{S^2-}\) \(\ce{HS^-}\) \(\ce{SO3^2-}\) \(\ce{HSO3^-}\) \(\ce{I^-}\) \(\ce{Fe^2+}\) \(\ce{F^-}\) \(\ce{Cl^-}\) \(\ce{H2C2O4}\) \(\ce{HC2O4^-}\) \(\ce{C2O4^2-}\)
\(\ce{MnO4^- + H^+}\) 反应 反应 反应 反应 反应 反应 不反应 反应(∆) 反应(∆) 反应(∆) 反应(∆)
\(\ce{MnO4^-}\) (中性) 反应 反应 反应 反应 不反应 不反应 不反应 不反应 不反应 不反应 不反应
\(\ce{NO3^- + H^+}\) 反应 反应 反应 反应 反应 反应 不反应 不反应 不反应 不反应 不反应
\(\ce{ClO^-}\) 反应 反应 反应 反应 反应 反应 不反应 不反应* 反应 反应 反应
\(\ce{Cr2O7^2- + H^+}\) 反应 反应 反应 反应 反应 反应 不反应 反应(∆) 反应 反应 反应
\(\ce{Fe^3+}\) 反应** 反应 反应 反应 反应 不反应 不反应 不反应 不反应 不反应 不反应
\(\ce{HClO}\) (带\(\ce{H+}\)的次氯酸) 反应 反应 反应 反应 反应 反应 不反应 反应 反应 反应 反应

歧化归中反应

\(\ce{S^2- 和SO3^2-}\)(酸性),\(\ce{Cl-和ClO-}\)(酸性),\(\ce{I-和IO3-}\)(酸性)等

\[\ce{3NO2^- + 2H+ -> 2NO ^ + NO3^- + H2O} \]

\[\ce{S2O3^2- + 2H+ -> S v + SO2 ^ + H2O} \]

配合反应

\(\ce{Fe^3+和SCN-,CN-}\)

\[\ce{Fe^3+ + 3SCN^- -> Fe(SCN)3} \]

\[\ce{Fe^3+ + 6CN^- -> [Fe(CN)6]^3-} \]

\(\ce{Fe^2+和[Fe(CN)6]^3-}\)

\[\ce{3Fe^2+ + 2[Fe(CN)6]^3- -> Fe3[Fe(CN)6]2 v} \]

\(\ce{Ag+和NH3·H2O}\)

\[\ce{Ag+ + 2NH3\cdot H2O -> [Ag(NH3)2]+ + 2H2O} \]

\(\ce{Cu^2+和NH3·H2O}\)

\[\ce{Cu^2+ + 4NH3\cdot H2O -> [Cu(NH3)4]^2+ + 4H2O} \]

\(\ce{Fe^3+和C6H5O-}\)

\[\ce{Fe^3+ + 6C6H5O^- -> [Fe(C6H5O)6]^3-} \]

一个配合物相关的复分解反应

\[\ce{[Ag(NH3)2]+ + 2H+ -> Ag+ + 2NH4+} \]

双水解

阳离子对应的碱极弱(且难溶),或阴离子对应的酸极弱(且易挥发/分解),并且生成物有 沉淀 或 气体 逸出,将平衡彻底拉向右端,这时不能共存

\(\ce{Al^3+}\)

\[\ce{Al^3+ + 3HCO3^- -> Al(OH)3 v + 3CO2 ^} \]

\[\ce{2Al^3+ + 3CO3^2- + 3H2O -> 2Al(OH)3 v + 3CO2 ^} \]

\[\ce{Al^3+ + 3ClO^- + 3H2O -> Al(OH)3 v + 3HClO} \]

\[\ce{2Al^3+ + 3SiO3^2- + 6H2O -> 2Al(OH)3 v + 3H2SiO3 v} \]

\[\ce{Al^3+ + 3[Al(OH)4]^- -> 4Al(OH)3 v} \]

(酸碱中和)

\[\ce{Al^3+ + 3HS^- + 3H2O -> Al(OH)3 v + 3H2S ^} \]

\[\ce{2Al^3+ + 3S^2- + 6H2O -> 2Al(OH)3 v + 3H2S ^} \]

\(\ce{Fe^3+}\)

\[\ce{Fe^3+ + 3HCO3^- -> Fe(OH)3 v + 3CO2 ^} \]

\[\ce{2Fe^3+ + 3CO3^2- + 3H2O -> 2Fe(OH)3 v + 3CO2 ^} \]

\[\ce{Fe^3+ + 3ClO^- + 3H2O -> Fe(OH)3 v + 3HClO} \]

\[\ce{2Fe^3+ + 3SiO3^2- + 6H2O -> 2Fe(OH)3 v + 3H2SiO3 v} \]

\[\ce{Fe^3+ + 3[Al(OH)4]^- -> Fe(OH)3 v + 3Al(OH)3 v} \]

(酸碱中和)

\[\ce{2Fe^3+ + 3S^2- -> 2FeS v + S v} \]

(氧化还原)

\[\ce{2Fe^3+ + 3HS^- -> 2FeS v + S v + 3H+} \]

(氧化还原)

\(\ce{NH3}\)

\[\ce{NH4+ + [Al(OH)4]^- -> Al(OH)3 v + NH3\cdot H2O} \]

中性溶液中的剧烈水解

\[\ce{Al^3+ + 3H2O <=> Al(OH)3 v + 3H+} \]

\[\ce{Fe^3+ + 3H2O <=> Fe(OH)3 v + 3H+} \]

氧化还原大全

氧化剂 酸性条件下不能反应的还原剂 无酸(中性/碱性)条件下不能反应的还原剂
\(\ce{F2}\) \(\ce{F-}\)(同素不反应)、\(\ce{LiAlH4}\)\(\ce{NaBH4}\)(遇水优先剧烈水解) 同左
\(\ce{O3}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需点燃或加热)、\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\) 同左
\(\ce{O2}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)\(\ce{SO2}\)\(\ce{HSO3-}\)\(\ce{SO3^2-}\)\(\ce{H2S}\)\(\ce{HS-}\)\(\ce{S^2-}\)\(\ce{Fe^2+}\)\(\ce{I-}\)\(\ce{S2O3^2-}\)\(\ce{Cl-}\)\(\ce{Br-}\)\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\)(常温下均不反应) 同左
\(\ce{Cl2}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需光照/加热)、\(\ce{Cl-}\)(同素不反应)、\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\) 同左
\(\ce{Br2}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{Cl-}\)(核心,\(\ce{Br2}\)无法氧化\(\ce{Cl-}\))、\(\ce{Br-}\)(同素不反应)、\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\) 同左
\(\ce{KMnO4}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)\(\ce{Fe^2+}\)\(\ce{Cl-}\)\(\ce{Br-}\)\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\)(中性下被还原为\(\ce{MnO2}\),氧化性大减,无法氧化\(\ce{Cl-、Br-、Fe^2+}\)
\(\ce{K2Cr2O7}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{Cl-}\)(标准状态下无法氧化)、\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\) \(\ce{活泼金属}\)外几乎全部:\(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)\(\ce{SO2}\)\(\ce{HSO3-}\)\(\ce{SO3^2-}\)\(\ce{H2S}\)\(\ce{HS-}\)\(\ce{S^2-}\)\(\ce{Fe^2+}\)\(\ce{I-}\)\(\ce{S2O3^2-}\)\(\ce{Cl-}\)\(\ce{Br-}\)\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\)(无酸时转化为\(\ce{CrO4^2-}\),氧化性极弱)
\(\ce{FeCl3}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{Fe^2+}\)(相邻价态)、\(\ce{Cl-}\)(自身阴离子)、\(\ce{Br-}\)(无法氧化)、\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\) 同左
\(\ce{NaClO}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)\(\ce{Cl-}\)\(\ce{Br-}\)\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\)(碱性下氧化性温和,不能氧化卤素离子)
\(\ce{Ca(ClO)2}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)\(\ce{Cl-}\)\(\ce{Br-}\)\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\)
\(\ce{HClO}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)\(\ce{Cl-}\)\(\ce{Br-}\)\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\)
\(\ce{Na2O2}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{F-}\)\(\ce{Cl-}\)\(\ce{Br-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\) 同左
\(\ce{H2O2}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{F-}\)\(\ce{Cl-}\)\(\ce{Br-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\) 同左
浓硫酸 \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{Fe^2+}\)(常温下不反应)、\(\ce{SO2}\)\(\ce{HSO3-}\)\(\ce{SO3^2-}\)(相邻价态)、\(\ce{F-}\)\(\ce{Cl-}\)(常温下不反应,热浓可反应)、\(\ce{活泼金属}\)中的\(\ce{Al}\)\(\ce{Fe}\)(常温下钝化)、\(\ce{LiAlH4}\)\(\ce{NaBH4}\) 不适用(浓硫酸本身提供\(\ce{H+}\)
\(\ce{MnO2}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{Cl-}\)(常温不反应,需浓盐酸并加热)、\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\) \(\ce{活泼金属}\)外几乎全部:\(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)\(\ce{SO2}\)\(\ce{HSO3-}\)\(\ce{SO3^2-}\)\(\ce{H2S}\)\(\ce{HS-}\)\(\ce{S^2-}\)\(\ce{Fe^2+}\)\(\ce{I-}\)\(\ce{S2O3^2-}\)\(\ce{Cl-}\)\(\ce{Br-}\)\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\)(无酸时几乎无氧化性)
\(\ce{ClO2}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{F-}\)\(\ce{Cl-}\)\(\ce{Br-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\) 同左
\(\ce{K2FeO4}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{F-}\)\(\ce{Cl-}\)\(\ce{Br-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\) 同左
\(\ce{KClO3}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{F-}\)\(\ce{Cl-}\)(常温下不反应)、\(\ce{LiAlH4}\)\(\ce{NaBH4}\) \(\ce{活泼金属}\)外几乎全部:\(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)\(\ce{SO2}\)\(\ce{HSO3-}\)\(\ce{SO3^2-}\)\(\ce{H2S}\)\(\ce{HS-}\)\(\ce{S^2-}\)\(\ce{Fe^2+}\)\(\ce{I-}\)\(\ce{S2O3^2-}\)\(\ce{Cl-}\)\(\ce{Br-}\)\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\)(无酸时常温几乎无氧化性)
\(\ce{S2O8^2-}\) \(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)(常温下不反应,需加热)、\(\ce{F-}\)\(\ce{Cl-}\)(常温不反应)、\(\ce{LiAlH4}\)\(\ce{NaBH4}\) \(\ce{活泼金属}\)外几乎全部:\(\ce{H2}\)\(\ce{C}\)\(\ce{CO}\)\(\ce{SO2}\)\(\ce{HSO3-}\)\(\ce{SO3^2-}\)\(\ce{H2S}\)\(\ce{HS-}\)\(\ce{S^2-}\)\(\ce{Fe^2+}\)\(\ce{I-}\)\(\ce{S2O3^2-}\)\(\ce{Cl-}\)\(\ce{Br-}\)\(\ce{F-}\)\(\ce{LiAlH4}\)\(\ce{NaBH4}\)(无酸时氧化能力大幅下降)
posted @ 2026-09-08 20:40  fnoihzhyan  阅读(25)  评论(0)    收藏  举报