How do you calculate the solubility at 25°C in grams per liter of silver iodide in an aqueous solution that is 0.15 M inpotassium iodide and 0.25 M in ammonia.

A 230 g sample of a compound contains 136.6 g of carbon, 26.4 g of hydrogen, and 31.8 g of nitrogen. The rest is oxygen. What is the mass percent of oxygen in the compound?

To calculate the solubility of silver iodide (AgI) in grams per liter at 25°C in the given aqueous solution, you need to consider the common ion effect. In this case, the common ion is the iodide ion (I-) from potassium iodide (KI).

Here is a step-by-step approach to solving the problem:

1. Identify the balanced chemical equation for the dissolution of silver iodide (AgI) in water:
AgI(s) ↔ Ag+(aq) + I-(aq)

2. Write the solubility product expression (Ksp) for the dissolution reaction:
Ksp = [Ag+][I-]

3. Determine the initial concentration of iodide ions (I-) in the aqueous solution. Given that the solution is 0.15 M in potassium iodide (KI), the concentration of iodide ions will also be 0.15 M.

4. Since silver iodide is sparingly soluble and undergoes limited dissolution, it can be assumed that the concentration of iodide ions will remain approximately constant during the dissolution process. Thus, the concentration of iodide ions will be the same in the equilibrium solution.

5. Determine the concentration of silver ions (Ag+) using the stoichiometry of the balanced equation. In this case, since the ratio of silver ions to iodide ions is 1:1, the equilibrium concentration of silver ions is also 0.15 M.

6. Substitute the equilibrium concentrations of silver ions and iodide ions into the solubility product expression:
Ksp = [0.15][0.15]

7. Calculate the solubility product constant (Ksp) by multiplying the equilibrium concentrations of silver ions and iodide ions:
Ksp = 0.0225

8. To calculate the solubility of silver iodide (AgI) in grams per liter, we first need to determine the concentration of dissolved silver ions (Ag+) in the saturated solution. The concentration of silver ions (Ag+) is equal to the solubility of silver iodide (AgI) in moles per liter, as they have a 1:1 stoichiometric ratio in the balanced equation.

9. Use the molar mass of silver (Ag) to convert the concentration of silver ions from moles per liter to grams per liter.

10. Finally, calculate the solubility of silver iodide (AgI) in grams per liter by dividing the molar mass of silver iodide (AgI) by the concentration of silver ions (Ag+) in grams per liter.

Remember to consider the temperature, as the solubility of most substances, including silver iodide, can change with temperature.