Net Ionic Equations · 净离子方程式
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| net ionic equation/net aɪˈɒnɪk ɪˈkweɪʒn/ | 净离子方程式 | jìng lí zi fāng chéng shì |
| spectator ions/spekˈteɪtə ˈaɪɒnz/ | 旁观离子 | páng guān lí zi |
Cutting a reaction to its core
- Mix two clear solutions and a solid suddenly appears.
- But most of the dissolved ions just drift by, unchanged.
- Only a few actually take part in the change.
- We can strip an equation down to just those.
把反应削到核心
- 混合两份清澈的溶液,忽然出现一块固体。
- 但大多数溶解的离子只是漂过,毫无变化。
- 只有少数真正参与了这场变化。
- 我们能把方程削减到只剩它们。
Three ways to write it
- The molecular equation shows whole compounds.
- The complete ionic equation splits every dissolved ionic compound into ions.
- The net ionic equation 净离子方程式 keeps only the ions that react.
三种写法
- 分子方程显示完整的化合物。
- 完全离子方程把每一个溶解的离子化合物拆成离子。
- 净离子方程式只保留发生反应的离子。
Which species is split into ions in the complete ionic equation? · 在完全离子方程式中，哪种物种被拆分为离子？
Only dissolved (aqueous) ionic compounds are written as ions. · 只有溶解的（水溶液）离子化合物才写成离子形式。
Spectator ions cancel
- Spectator ions 旁观离子 appear unchanged on both sides.
- Cancel them, just like identical terms in algebra.
- What remains is the net ionic equation.
旁观离子相消
- 旁观离子在两边原封不动地出现。
- 把它们消去,就像代数里相同的项一样。
- 剩下的就是净离子方程式。
A spectator ion is one that... · 旁观离子是指...
Spectators do not change, so they cancel out. · 旁观者不发生变化，因此会被抵消。
After cancelling spectator ions, what remains is the ____ ionic equation. · 抵消旁观离子后，剩下的是____离子方程式。
The leftover reacting ions form the net ionic equation. · 剩余的参与反应的离子构成了净离子方程式。
The real change
- The net ionic equation shows only the species that actually change.
- For a precipitate, it is the two ions that join to form the solid.
- It captures the true chemistry, stripped of clutter.
真正的变化
- 净离子方程式只显示真正发生变化的物种。
- 对于沉淀,就是结合成固体的那两个离子。
- 它抓住真正的化学,去除杂乱。
Write a net ionic equation · 写出净离子方程式
Strip a reaction down to the ions that actually react. · 将反应简化为实际参与反应的离子。
A solid precipitate is written as separate ions in the net ionic equation. · 在净离子方程式中，固体沉淀应写成单独的离子。
Only aqueous ions split; a solid stays as one whole formula. · 只有水溶液离子拆分；固体保持为一个完整的化学式。
A correct net ionic equation must balance both atoms and charge. · 正确的净离子方程式必须在原子和电荷两方面都配平。
Both mass and charge are conserved. · 质量和电荷均守恒。
$\text{AgNO}_3 + \text{NaCl} \to \text{AgCl} + \text{NaNO}_3$.
- $\text{Na}^+$ and $\text{NO}_3^-$ are spectators, so cancel them.
- Net ionic equation: $\text{Ag}^+ + \text{Cl}^- \to \text{AgCl}$.
$\text{AgNO}_3 + \text{NaCl} \to \text{AgCl} + \text{NaNO}_3$。
- $\text{Na}^+$ 和 $\text{NO}_3^-$ 是旁观离子,消去它们。
- 净离子方程式:$\text{Ag}^+ + \text{Cl}^- \to \text{AgCl}$。
For · 支持 $\text{Ag}^+ + \text{NO}_3^- + \text{Na}^+ + \text{Cl}^- \to \text{AgCl} + \text{Na}^+ + \text{NO}_3^-$, the net ionic equation is... · 对于$\text{Ag}^+ + \text{NO}_3^- + \text{Na}^+ + \text{Cl}^- \to \text{AgCl} + \text{Na}^+ + \text{NO}_3^-$，净离子方程式是...
$\text{Na}^+$ and $\text{NO}_3^-$ are spectators; only Ag and Cl react. · $\text{Na}^+$和$\text{NO}_3^-$是旁观离子；只有Ag和Cl发生反应。
Only aqueous (dissolved) ionic compounds split into ions -- solids, liquids, and gases stay whole. Spectator ions are identical on both sides, so cancel only those. And the net ionic equation must still balance in both atoms and charge.
只有水溶液中(溶解的)离子化合物才拆成离子——固体、液体和气体保持完整。旁观离子在两边完全相同,只消去那些。而且净离子方程式必须在原子和电荷两方面都配平。
A net ionic equation strips a reaction to the ions that actually change. Split aqueous ionic compounds into ions, cancel the spectator ions that are identical on both sides, and keep the rest -- like $\text{Ag}^+ + \text{Cl}^- \to \text{AgCl}$. The result must balance atoms and charge.
净离子方程式把反应削减到真正变化的离子。把水溶液中的离子化合物拆成离子,消去两边完全相同的旁观离子,保留其余——如 $\text{Ag}^+ + \text{Cl}^- \to \text{AgCl}$。结果必须在原子和电荷上都配平。