Understanding the Dissociation
* K₂CrO₄ (Potassium Chromate) is a strong electrolyte, meaning it fully dissociates into ions when dissolved in water.
* The dissociation reaction looks like this:
K₂CrO₄ (aq) → 2K⁺ (aq) + CrO₄²⁻ (aq)
The Key Point
* One formula unit of K₂CrO₄ produces three ions: 2 potassium ions (K⁺) and 1 chromate ion (CrO₄²⁻).
Therefore, 1 mg of K₂CrO₄, when fully dissolved, will have three times the number of ions compared to the original number of formula units.
Example:
Let's say 1 mg of K₂CrO₄ contains 100 formula units. After dissolving:
* There will be 100 x 2 = 200 potassium ions (K⁺).
* There will be 100 x 1 = 100 chromate ions (CrO₄²⁻).
* Total ions: 200 + 100 = 300 ions
* The number of ions (300) is three times the number of formula units (100).
Important Note: This explanation assumes complete ionization in water. In reality, slight deviations might occur due to factors like ion pairing. However, the principle of the 1:3 ion-to-formula unit ratio holds true for strong electrolytes like potassium chromate.
