To complete and balance the precipitation reaction, we need to follow these steps:
### Step 1: Write the Dissociation of Reactants
First, we need to write the dissociation reactions of the reactants in aqueous solution.
1. Copper(II) chloride (CuCl₂):
[tex]\[ \text{CuCl}_2(aq) \rightarrow \text{Cu}^{2+}(aq) + 2\text{Cl}^-(aq) \][/tex]
2. Sodium carbonate (Na₂CO₃):
[tex]\[ \text{Na}_2\text{CO}_3(aq) \rightarrow 2\text{Na}^+(aq) + \text{CO}_3^{2-}(aq) \][/tex]
### Step 2: Identify the Possible Products
When these ions are in solution, they can recombine to form new compounds. The possible products are:
- Copper(II) carbonate (CuCO₃):
- Sodium chloride (NaCl):
### Step 3: Consider the Solubility Rules
To determine which products will precipitate out of solution, we need to refer to the solubility rules for common salts:
- Most carbonates ([tex]\(\text{CO}_3^{2-}\)[/tex]) are insoluble in water, except those of alkali metals (like Na⁺) and ammonium.
- All chlorides ([tex]\(\text{Cl}^-\)[/tex]) are soluble, except those of silver (Ag⁺), lead (Pb²⁺), and mercury (Hg₂²⁺).
Based on these rules:
- Copper(II) carbonate (CuCO₃) is insoluble and will precipitate.
- Sodium chloride (NaCl) is soluble and will remain in aqueous solution.
### Step 4: Write the Complete Reaction
Now, we can write the complete and balanced precipitation reaction. The formation of the products involves the combination of Cu²⁺ and CO₃²⁻ to form CuCO₃ (solid), and Na⁺ with Cl⁻ to form NaCl (aqueous).
[tex]\[ \text{CuCl}_2(aq) + \text{Na}_2\text{CO}_3(aq) \longrightarrow \text{CuCO}_3(s) + 2\text{NaCl}(aq) \][/tex]
### Step 5: Balance the Reaction
The reaction must be balanced to ensure the conservation of mass and charge. We check the number of atoms of each element on both sides of the equation:
- Copper (Cu): 1 atom on both sides.
- Chlorine (Cl): 2 atoms on both sides.
- Sodium (Na): 2 atoms on both sides.
- Carbon (C): 1 atom on both sides.
- Oxygen (O): 3 atoms on both sides.
The equation is already balanced with these coefficients.
### Final Answer
The completed and balanced precipitation reaction with physical states included is:
[tex]\[ \text{CuCl}_2(aq) + \text{Na}_2\text{CO}_3(aq) \longrightarrow \text{CuCO}_3(s) + 2\text{NaCl}(aq) \][/tex]
