Final answer:
The temperature at which all of the potassium nitrate has just been dissolved in water is the saturation temperature of potassium nitrate in water.
Step-by-step explanation:
In this question, we are given a mixture of 735.4 g of potassium nitrate and 700.0 grams of water. We need to determine the temperature at which all of the potassium nitrate has just been dissolved.
The solubility of potassium nitrate in water increases with an increase in temperature. This means that more potassium nitrate can dissolve in water at higher temperatures.
To find the temperature at which all of the potassium nitrate has just been dissolved, we need to heat the mixture until no more potassium nitrate can dissolve. This is the point of saturation, where the solubility of potassium nitrate in water is at its maximum.
Therefore, the temperature at which this occurs is the saturation temperature of potassium nitrate in water.