Understanding the Concept

* Molarity: Molarity (M) is a unit of concentration that represents the number of moles of solute per liter of solution.

* Barium Chloride (BaCl₂) : Barium chloride is an ionic compound that dissociates in water to form barium ions (Ba²⁺) and chloride ions (Cl⁻) in a 1:2 ratio.

Steps

1. Dissociation Equation:

BaCl₂(aq) → Ba²⁺(aq) + 2Cl⁻(aq)

2. Moles of Barium Chloride:

* We have 100 ml of a 500 M barium chloride solution.

* Convert ml to liters: 100 ml * (1 L / 1000 ml) = 0.1 L

* Moles of BaCl₂ = Molarity * Volume (in liters) = 500 M * 0.1 L = 50 moles

3. Moles of Chloride Ions:

* From the dissociation equation, 1 mole of BaCl₂ produces 2 moles of Cl⁻.

* Moles of Cl⁻ = 50 moles BaCl₂ * (2 moles Cl⁻ / 1 mole BaCl₂) = 100 moles Cl⁻

4. Molarity of Chloride Ions:

* Molarity of Cl⁻ = Moles of Cl⁻ / Volume of solution (in liters) = 100 moles / 0.1 L = 1000 M

Therefore, the molarity of chloride ion in 100 ml of a 500 M barium chloride solution is 1000 M.