A solution is prepared by dissolving 130 g of NaNO3 in 100 g of water at 80°C. The solution is cooled to 0°C. How many grams of compound remain in solution?
How may grams of solid are formed?
Didn't I see that Bob Pursley had worked this problem earlier?
To determine how many grams of compound remain in solution, we need to know the solubility of NaNO3 at 0°C. This can be found in a solubility table or reference book. Let's assume that the solubility of NaNO3 at 0°C is 180 g per 100 g of water.
First, we need to calculate how much NaNO3 was dissolved in the solution at 80°C. This is equal to the initial mass of NaNO3 minus the mass of NaNO3 that precipitated out as the solution cooled.
Initial mass of NaNO3 = 130 g
Initial mass of water = 100 g
To calculate the mass of NaNO3 that precipitated out, we need to find the mass of water that was evaporated. This can be done using the formula:
Mass of water evaporated = (initial mass of water) - (final mass of water)
Mass of water evaporated = 100 g - (final mass of water)
To find the final mass of water, we can use the fact that the solution is at 0°C:
Density of water at 0°C = 0.9998 g/mL
Using the density, we can convert the volume of water to its mass:
Initial volume of water = (initial mass of water) / (density of water at 0°C)
Initial volume of water = 100 g / 0.9998 g/mL
Now, we can find the final mass of water by using the fact that the volume of water remains the same when it is cooled:
Final mass of water = (mass of water at 80°C) = (initial volume of water) * (density of water at 0°C)
Now we can calculate the mass of NaNO3 that precipitated out using the formula:
Mass of NaNO3 that precipitated out = (mass of water evaporated) * (solubility of NaNO3 at 0°C)
Finally, we can find the mass of NaNO3 remaining in solution by subtracting the mass of NaNO3 that precipitated out from the initial mass of NaNO3:
Mass of NaNO3 remaining in solution = (initial mass of NaNO3) - (mass of NaNO3 that precipitated out)
To determine how many grams of solid are formed, we can simply subtract the mass of NaNO3 remaining in solution from the initial mass of NaNO3:
Mass of solid formed = (initial mass of NaNO3) - (mass of NaNO3 remaining in solution)
By following these calculations and using the given solubility of NaNO3 at 0°C, you can find the grams of compound that remain in solution and the grams of solid formed.