Here's how to calculate the percentage concentration of each solute in the solution:

Understanding Percentage Concentration

Percentage concentration (also known as mass/volume percentage) expresses the amount of solute (in grams) dissolved in 100 mL of solution.

Calculations

1. Total Mass of Solution:

* Mass of potassium iodate (KI) = 3.50 g

* Mass of potassium hydroxide (KOH) = 6.23 g

* Mass of water (H₂O) = 805.05 g

* Total mass of solution = 3.50 g + 6.23 g + 805.05 g = 814.78 g

2. Percentage Concentration of Potassium Iodate:

* (Mass of KI / Total mass of solution) * 100%

* (3.50 g / 814.78 g) * 100% = 0.43%

3. Percentage Concentration of Potassium Hydroxide:

* (Mass of KOH / Total mass of solution) * 100%

* (6.23 g / 814.78 g) * 100% = 0.76%

Important Note: The solution is likely to be very dilute due to the large amount of water.

Let me know if you'd like to calculate the concentration in different units (like molarity or molality)!