pH and Solubility · pH与溶解度
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| solubility/ˌsɒljuːˈbɪlɪti/ | 溶解度 | róng jiě dù |
Acid that dissolves the insoluble
- Some "insoluble" salts vanish when you add acid.
- Chalk fizzes and disappears in vinegar.
- The acid quietly removes one of the salt's ions.
- That removal pulls more solid into solution.
溶解"不溶物"的酸
- 有些"不溶"的盐在你加酸时消失了。
- 粉笔在醋里冒泡并消失。
- 酸悄悄地移走了盐的一种离子。
- 那次移走把更多固体拉进溶液。
Salts with basic anions
- Salts whose anion is a weak base dissolve more in acid.
- Carbonates, hydroxides, and fluorides are examples.
- Their anion reacts with the added $\text{H}^+$.
带碱性阴离子的盐
- 阴离子是弱碱的盐在酸中溶解得更多。
- 碳酸盐、氢氧化物和氟化物都是例子。
- 它们的阴离子与加入的 $\text{H}^+$ 反应。
Which type of salt dissolves more as the pH is lowered? · 随着pH降低，哪种类型的盐溶解得更多？
A basic anion reacts with added acid, so more dissolves. · 碱性阴离子与被加入的酸反应，因此溶解更多。
Salts of weak-acid anions, such as carbonates and ____, dissolve more in acid. · 弱酸阴离子的盐，如碳酸盐和 ____，在酸中更易溶解。
Hydroxide and carbonate anions are basic, so acid dissolves them. · 氢氧化物和碳酸根阴离子呈碱性，因此酸能溶解它们。
Removing an ion shifts the balance
- Acid consumes the dissolved anion.
- That drops $Q$ below $K_{sp}$, so more solid dissolves.
- It is Le Chatelier applied to solubility 溶解度.
移走一个离子就打破平衡
- 酸消耗溶解的阴离子。
- 那把 $Q$ 降到 $K_{sp}$ 之下,所以更多固体溶解。
- 这是勒沙特列应用于溶解度。
Adding acid removes the anion, which drops $Q$ below $K_{sp}$, so the solid... · 加入酸会移除阴离子，导致$Q$降至$K_{sp}$以下，因此固体……
With $Q < K_{sp}$, more solid dissolves to restore equilibrium. · 与$Q < K_{sp}$相比，更多固体会溶解以恢复平衡。
The pH effect on solubility is an example of Le Chatelier's principle. · pH 对溶解度的影响是勒夏特列原理的一个例子。
Removing an ion shifts the dissolving equilibrium forward. · 移除离子会使溶解平衡向正向移动。
Not every salt cares
- Salts of strong-acid anions (like $\text{Cl}^-$) are unaffected by pH.
- Their anion is not a base, so acid does nothing.
- Only basic anions respond to pH.
并非每种盐都在意
- 强酸阴离子的盐(如 $\text{Cl}^-$)不受 pH 影响。
- 它们的阴离子不是碱,所以酸不起作用。
- 只有碱性阴离子对 pH 作出响应。
The solubility of $\text{AgCl}$ changes strongly with pH. · $\text{AgCl}$的溶解度受pH影响很大。
$\text{Cl}^-$ is not a base, so pH has little effect. · $\text{Cl}^-$不是碱，因此pH对其影响很小。
Does $\text{CaCO}_3$ dissolve more in acid or in neutral water?
- Acid reacts with the carbonate ion.
- So $\text{CaCO}_3$ dissolves more in acid.
$\text{CaCO}_3$ 在酸中还是在中性水中溶解得更多?
- 酸与碳酸根离子反应。
- 所以 $\text{CaCO}_3$ 在酸中溶解得更多。
Does pH change solubility? · pH是否改变溶解度？
Sort each salt by whether lowering the pH makes it more soluble. · 根据降低pH是否使每种盐更易溶，对其进行排序。
$\text{CaCO}_3$ dissolves more in... · $\text{CaCO}_3$在……中溶解得更多
Acid reacts with the basic carbonate ion, dissolving more solid. · 酸与碱性碳酸根离子反应，溶解更多固体。
Only salts with a basic anion (from a weak acid, like carbonate or hydroxide) dissolve more in acid -- salts of strong-acid anions like chloride do not respond. Lowering the pH removes the anion, pulling more solid in. This is just Le Chatelier acting on the dissolving equilibrium.
只有带碱性阴离子(来自弱酸,如碳酸根或氢氧根)的盐在酸中溶解得更多——氯离子这类强酸阴离子的盐不响应。降低 pH 会移走阴离子,把更多固体拉进来。这只是勒沙特列作用于溶解平衡。
Salts with a basic anion (carbonates, hydroxides) dissolve more in acid: the added $\text{H}^+$ removes the anion, dropping $Q$ below $K_{sp}$ so more solid dissolves. Salts of strong-acid anions like chloride are unaffected -- it is Le Chatelier acting on solubility.
带碱性阴离子(碳酸盐、氢氧化物)的盐在酸中溶解得更多:加入的 $\text{H}^+$ 移走阴离子,把 $Q$ 降到 $K_{sp}$ 之下,所以更多固体溶解。氯离子这类强酸阴离子的盐不受影响——这是勒沙特列作用于溶解度。