Question

Fill in this table: $$ \begin{array}{lll} & & \text { Soluble or } \\ \text { Name } & \text { Formula } & \text { insoluble } \\ \hline \text { Sodium phosphate } & & \\ & \mathrm{Ba}\left(\mathrm{CH}_{3} \mathrm{CO}_{2}\right)_{2} & \\ & \left(\mathrm{NH}_{4}\right)_{2} \mathrm{~S} & \\ \text { Iron(II) carbonate } & & \\ \text { Mercury(II) chloride } & & \\ & \mathrm{Co}(\mathrm{OH})_{2} & \\ & \mathrm{HgCl} & \\ \hline \end{array} $$

Short answer

The completed table is as follows: $$ \begin{array}{lll} & & \text { Soluble or } \\\ \text { Name } & \text { Formula } & \text { insoluble } \\\ \hline \text { Sodium phosphate } & \mathrm{Na}_3 \mathrm{PO}_4 & \text { Soluble } \\\ & \mathrm{Ba}\left(\mathrm{CH}_{3} \mathrm{CO}_{2}\right)_{2} & \text { Soluble } \\\ & \left(\mathrm{NH}_{4}\right)_{2} \mathrm{~S} & \text { Soluble } \\\ \text { Iron(II) carbonate } & \mathrm{FeCO}_3 & \text { Insoluble } \\\ \text { Mercury(II) chloride } & \mathrm{HgCl}_2 & \text { Insoluble } \\\ & \mathrm{Co}(\mathrm{OH})_{2} & \text { Insoluble } \\\ & \mathrm{HgCl} & \text { Insoluble } \\\ \hline \end{array} $$

Step-by-step solution

Determine Chemical Formulas for Named Compounds

First, we need to find the chemical formulas for Sodium phosphate, Iron(II) carbonate, and Mercury(II) chloride. 1. Sodium phosphate: To find the formula for sodium phosphate, we need to identify the ions involved: sodium (Na^+) and phosphate (PO_4^{3-}). Combining these ions, we get Na_3PO_4 as the formula. 2. Iron(II) carbonate: Iron(II) indicates that the iron ion has a charge of +2 (Fe^2+). Carbonate is CO_3^{2-}. Combining these ions, we get FeCO_3 as the formula. 3. Mercury(II) chloride: Mercury(II) indicates that the mercury ion has a charge of +2 (Hg^2+). Chloride is Cl^-. Combining these ions, we get HgCl_2 as the formula.

Determine Solubility of Compounds

Now, we will use solubility rules to determine if each compound is soluble or insoluble. 1. Sodium phosphate (Na_3PO_4): Sodium compounds are generally soluble. Therefore, Na_3PO_4 is soluble. 2. Barium acetate (Ba(CH_3CO_2)_2): Barium compounds are generally soluble, with a few exceptions. This compound does not fall under the exceptions. Therefore, Ba(CH_3CO_2)_2 is soluble. 3. Ammonium sulfide ((NH_4)_2S): Compounds containing ammonium ions are generally soluble. Therefore, (NH_4)_2S is soluble. 4. Iron(II) carbonate (FeCO_3): Most carbonate salts are insoluble, with a few exceptions. This compound does not fall under the exceptions. Therefore, FeCO_3 is insoluble. 5. Mercury(II) chloride (HgCl_2): Most chloride salts are soluble, but mercury(II) chloride is an exception. Therefore, HgCl_2 is insoluble. 6. Cobalt(II) hydroxide (Co(OH)_2): most hydroxide salts are insoluble, with a few exceptions. This compound does not fall under the exceptions. Therefore, Co(OH)_2 is insoluble. 7. Mercury(I) chloride (HgCl): Most chloride salts are soluble, but mercury(I) chloride is an exception. Therefore, HgCl is insoluble. Now, we can fill in the table with the missing information: $$ \begin{array}{lll} & & \text { Soluble or } \\\ \text { Name } & \text { Formula } & \text { insoluble } \\\ \hline \text { Sodium phosphate } & \mathrm{Na}_3 \mathrm{PO}_4 & \text { Soluble } \\\ & \mathrm{Ba}\left(\mathrm{CH}_{3} \mathrm{CO}_{2}\right)_{2} & \text { Soluble } \\\ & \left(\mathrm{NH}_{4}\right)_{2} \mathrm{~S} & \text { Soluble } \\\ \text { Iron(II) carbonate } & \mathrm{FeCO}_3 & \text { Insoluble } \\\ \text { Mercury(II) chloride } & \mathrm{HgCl}_2 & \text { Insoluble } \\\ & \mathrm{Co}(\mathrm{OH})_{2} & \text { Insoluble } \\\ & \mathrm{HgCl} & \text { Insoluble } \\\ \hline \end{array} $$

Key concepts

Chemical Formulas

Chemical formulas are essential for understanding how elements combine to form compounds. Each formula represents the composition of a molecule using symbols and numbers. For example:

- **Sodium Phosphate (Na₃PO₄)**: This consists of sodium ions, Na⁺, and phosphate ions, PO₄³⁻. The formula shows that three sodium ions combine with one phosphate ion to balance the charge. - **Iron(II) Carbonate (FeCO₃)**: Here, iron(II) indicates a +2 charge on iron (Fe²⁺), pairing with a carbonate ion, CO₃²⁻, to form the compound. - **Mercury(II) Chloride (HgCl₂)**: This involves mercury ions, Hg²⁺, and chloride ions, Cl⁻. The formula illustrates that one mercury ion pairs with two chloride ions.

Understanding the valency and charges of ions helps in forming correct chemical formulas, allowing us to predict the resulting compound.

Soluble and Insoluble Compounds

Solubility rules help determine whether a compound will dissolve in water. Here's a quick look at some general rules:

• **Sodium Compounds**: Generally, compounds with sodium (Na⁺) are soluble, like sodium phosphate (Na₃PO₄).
• **Barium Acetate (Ba(CH₃CO₂)₂)**: This is soluble as barium compounds typically dissolve except for a few exceptions.
• **Ammonium Compounds**: With ions like NH₄⁺, are usually soluble, as seen in ammonium sulfide ((NH₄)₂S).
• **Carbonates**: Most are insoluble unless they come with alkali metals or ammonium. Thus, iron(II) carbonate (FeCO₃) is insoluble.
• **Chlorides**: Typically soluble, but exceptions like mercury(II) chloride (HgCl₂) exist.
• **Hydroxides**: Cobalt(II) hydroxide (Co(OH)₂) is insoluble, with only a few soluble exceptions.

These rules simplify how we predict the behavior of compounds in solutions, crucial for experiments and industrial processes.

Ion Identification

Identifying ions within a compound is key to determining its properties and behavior. Ions are charged particles formed when atoms lose or gain electrons.

Here's how to identify them:

• **Sodium (Na⁺)**: A common cation, often combines with various anions to form soluble compounds.
• **Phosphate (PO₄³⁻)**: A polyatomic ion, combines with metal ions like sodium to form compounds such as sodium phosphate.
• **Iron (Fe²⁺)**: Known as iron(II), it indicates a specific oxidation state crucial for balancing with anions.
• **Chloride (Cl⁻)**: Generally forms soluble compounds, but exceptions like with mercury exist.

By recognizing these ions and their charges, you can predict the resulting compounds’ properties, making it easier to decide on their uses and interactions in chemistry.