100g of water are saturated with KNO3 at 50˚c. how many grams of KNO3 will crystallize out if the temperature cools to 40˚c.
solubility curve.
To determine the quantity of KNO3 that will crystallize out as the temperature cools from 50˚C to 40˚C, we need to refer to the solubility curve of KNO3.
A solubility curve shows the maximum amount of solute that can dissolve in a given amount of solvent at different temperatures.
Here are the steps to find the answer using the solubility curve:
1. Obtain the solubility curve of KNO3. This curve shows how much KNO3 can dissolve at different temperatures.
2. Locate the point representing the initial temperature, which is 50˚C, on the solubility curve. Draw a vertical line down from this point.
3. At the point where the vertical line intersects the solubility curve, identify the amount of KNO3 (in grams) that can dissolve in 100g of water at 50˚C. Let's say this value is X grams.
4. Draw a horizontal line from the point where the vertical line intersects the solubility curve to the y-axis (amount of KNO3 axis). This line represents X grams of KNO3.
5. Locate the point representing the final temperature, which is 40˚C, on the x-axis of the solubility curve.
6. Draw a horizontal line from the point representing the final temperature to the point where it intersects the line representing X grams of KNO3.
7. At the point where the horizontal line intersects the line representing X grams of KNO3, draw a vertical line down to the x-axis (amount of KNO3 axis). This line represents the amount of KNO3 (in grams) that will crystallize out at 40˚C.
8. Read the value on the x-axis where the vertical line intersects. This value represents the amount of KNO3 (in grams) that will crystallize out.
By following these steps and referring to the solubility curve, you will be able to determine the quantity of KNO3 that will crystallize out when the temperature cools from 50˚C to 40˚C.