Here's how to calculate the molarity of Cl- in the solution:

1. Calculate the moles of CaCl2:

* Molar mass of CaCl2: 40.08 g/mol (Ca) + 2 * 35.45 g/mol (Cl) = 110.98 g/mol

* Moles of CaCl2: (5.55 g CaCl2) / (110.98 g/mol CaCl2) = 0.05 mol CaCl2

2. Calculate the moles of Cl- ions:

* Stoichiometry: For every 1 mole of CaCl2, there are 2 moles of Cl- ions.

* Moles of Cl-: (0.05 mol CaCl2) * (2 mol Cl-/1 mol CaCl2) = 0.1 mol Cl-

3. Calculate the molarity of Cl-:

* Molarity: Moles of solute / Liters of solution

* Convert ml to L: 110 ml = 0.11 L

* Molarity of Cl-: (0.1 mol Cl-) / (0.11 L) = 0.91 M

Therefore, the molarity of Cl- in the solution is 0.91 M.