Question

Consider a solution with the following ions present: $$\mathrm{NO}_{3}^{-}, \mathrm{Pb}^{2+}, \mathrm{K}^{+}, \mathrm{Ag}^{+}, \mathrm{Cl}^{-}, \mathrm{SO}_{4}^{2-}, \mathrm{PO}_{4}^{3-}$$ All are allowed to react, and there are plenty available of each. List all of the solids that will form using the correct formulas in your explanation.

Short answer

The insoluble solids that will form in the solution are: 1. \(PbCl_2\) (Lead(II) chloride) 2. \(Pb_3(PO_4)_2\) (Lead(II) phosphate) 3. \(AgCl\) (Silver(I) chloride) 4. \(Ag_3PO_4\) (Silver(I) phosphate)

Step-by-step solution

Identify the cations and anions

In this exercise, we have the following ions: Cations: - \(Pb^{2+}\) (Lead) - \(K^{+}\) (Potassium) - \(Ag^{+}\) (Silver) Anions: - \(NO_3^-\) (Nitrate) - \(Cl^-\) (Chloride) - \(SO_4^{2-}\) (Sulfate) - \(PO_4^{3-}\) (Phosphate)

Combine the cations and anions to form salts

Now we will list all possible salts formed by the combination of these cations with anions: 1. \(Pb(NO_3)_2\) 2. \(PbCl_2\) 3. \(PbSO_4\) 4. \(Pb_3(PO_4)_2\) 5. \(KNO_3\) 6. \(KCl\) 7. \(K_2SO_4\) 8. \(K_3PO_4\) 9. \(AgNO_3\) 10. \(AgCl\) 11. \(Ag_2SO_4\) 12. \(Ag_3PO_4\)

Apply solubility rules to determine the insoluble salts

Now we will apply solubility rules to determine which of these salts are insoluble in water: 1. \(Pb(NO_3)_2\): All nitrates are soluble; hence this salt is soluble. 2. \(PbCl_2\): Lead(II) chloride is an exception to the general solubility of chlorides, so it is insoluble. 3. \(PbSO_4\): Lead(II) sulfate is an exception to the general solubility of sulfates, so it is slightly soluble, with limited contribution to precipitation. 4. \(Pb_3(PO_4)_2\): All but group 1 metal phosphates are insoluble, and since lead(II) phosphate is not a group 1 metal, it is insoluble. 5. \(KNO_3\): All nitrates are soluble; hence this salt is soluble. 6. \(KCl\): All chlorides are generally soluble, including potassium chloride, so it is soluble. 7. \(K_2SO_4\): All but certain group 2 metal sulfates are soluble; potassium sulfate is soluble. 8. \(K_3PO_4\): All group 1 metal phosphates, which include potassium phosphate, are soluble. 9. \(AgNO_3\): All nitrates are soluble; hence this salt is soluble. 10. \(AgCl\): Silver chloride is an exception to the general solubility of chlorides, so it is insoluble. 11. \(Ag_2SO_4\): Silver(I) sulfate is slightly soluble in water; its contribution to precipitation will be limited. 12. \(Ag_3PO_4\): Silver(I) phosphate is an exception to the general solubility of phosphates, so it is insoluble.

List the insoluble salts

Based on the solubility rules, these solids will form in the solution: 1. \(PbCl_2\) (Lead(II) chloride) 2. \(Pb_3(PO_4)_2\) (Lead(II) phosphate) 3. \(AgCl\) (Silver(I) chloride) 4. \(Ag_3PO_4\) (Silver(I) phosphate)

Key concepts

Insoluble Salts

In chemistry, salts are compounds formed from the reaction of acids and bases, composed of positive ions (cations) and negative ions (anions). Not all salts dissolve in water, although many do. Insoluble salts do not dissociate into their ions in a solution, which means they form a precipitate. Understanding the solubility of salts involves determining whether they dissolve completely, partially, or not at all.

• An insoluble salt remains as solid particles in the solution instead of breaking apart into ions.
• When a salt's solubility is very low, it is classified as insoluble. This characteristic is crucial in predicting the outcome of chemical reactions.
• In our exercise, salts like \(PbCl_2\), \(Pb_3(PO_4)_2\), and \(AgCl\) form insoluble compounds.

Recognizing insoluble salts helps us predict what solid compounds might form when different ionic solutions are mixed.

Cations and Anions

Cations and anions are ions with positive and negative charges, respectively. In solutions, these ions repel or attract each other depending on their charges, coming together to form neutral compounds. In any chemical reaction, the combination of specific cations and anions dictates the potential formation of new products.

• Cations in our exercise: \(Pb^{2+}\), \(K^{+}\), and \(Ag^{+}\) come from metals. They carry a positive charge due to the loss of electrons.
• Anions in our exercise: \(NO_3^-\), \(Cl^-\), \(SO_4^{2-}\), and \(PO_4^{3-}\) are typically non-metallic, gaining electrons to carry a negative charge.

Understanding these ions is essential in predicting the formation of specific insoluble salts such as lead chloride or silver phosphate.

Chemical Reactions

Chemical reactions involving ions often occur between ionic compounds in solutions, leading to the formation of precipitates, gases, or other products. These reactions are intrinsic to solubility rules, as the formation of a solid precipitate is one key reaction we can observe.Here is a simple structure of how these reactions might look:

• When \(Pb^{2+}\) reacts with \(Cl^-\), it forms \(PbCl_2\), which precipitates as an insoluble salt.
• Similarly, \(Ag^{+}\) with \(Cl^-\) produces \(AgCl\), another solid precipitate.

These reactions highlight how specific combinations of ions can lead to new solid formations, which do not remain in solution.

Solubility Exceptions

While general rules dictate the solubility of various ionic compounds, there are numerous exceptions. Knowing these helps in pinpointing which salts will precipitate in a chemical reaction.For example:

• Generally, chlorides are soluble, but \(PbCl_2\) is not, making it a solubility exception.
• Sulfates tend to dissolve well, yet \(PbSO_4\) is only slightly soluble.
• Most phosphates are insoluble with silver and lead salts being quite characteristic exceptions.

These exceptions must always be considered when defining reaction outcomes in chemistry. Being familiar with these rules and exceptions is crucial for predicting the correct results efficiently.