The reaction of calcium chloride (CaCl₂) with sodium oleate (C₁₇H₃₅COONa) is a double displacement reaction that forms an insoluble calcium oleate precipitate and sodium chloride (NaCl) in solution.

Here's the unbalanced equation:

CaCl₂ (aq) + C₁₇H₃₅COONa (aq) → (C₁₇H₃₅COO)₂Ca (s) + NaCl (aq)

To balance the equation:

1. Count the number of each atom on both sides:

* Ca: 1 on the left, 1 on the right

* Cl: 2 on the left, 1 on the right

* C: 17 on the left, 34 on the right

* H: 35 on the left, 70 on the right

* O: 2 on the left, 4 on the right

* Na: 1 on the left, 1 on the right

2. Adjust the coefficients to balance the atoms:

* Put a coefficient of 2 in front of C₁₇H₃₅COONa on the left side:

CaCl₂ (aq) + 2 C₁₇H₃₅COONa (aq) → (C₁₇H₃₅COO)₂Ca (s) + NaCl (aq)

* Put a coefficient of 2 in front of NaCl on the right side:

CaCl₂ (aq) + 2 C₁₇H₃₅COONa (aq) → (C₁₇H₃₅COO)₂Ca (s) + 2 NaCl (aq)

Now the equation is balanced:

CaCl₂ (aq) + 2 C₁₇H₃₅COONa (aq) → (C₁₇H₃₅COO)₂Ca (s) + 2 NaCl (aq)

Explanation:

* Calcium chloride (CaCl₂) is a soluble ionic compound.

* Sodium oleate (C₁₇H₃₅COONa) is the primary component of soap and is also soluble.

* Calcium oleate ((C₁₇H₃₅COO)₂Ca) is an insoluble salt that forms a precipitate, causing the familiar "soap scum" when soap is used in hard water containing calcium ions.

* Sodium chloride (NaCl) is table salt and remains dissolved.