One gram of pbcl2 is dissolved in 1.0 l of hot water. When the solution is cooled to 25degrees Celsius, will some of the pbcl2 crystallize out? If so, how much?
I just don't know where to start/ where to go with this problem
Any help is appreciated!!
Look up Ksp for PbCl2 and solve for solubility PbCl2 @ 25 C. (You will get solubility at 25C because that temperature is used for determining Ksp).
Then convert M to mols/L, then to grams/L. If the solubility is >1.0 g no ppt; if < 1.0 g, yes a crystallization will occur.
To determine whether some of the PbCl2 will crystallize out when the solution is cooled, we need to calculate the solubility of PbCl2 in water at 25 degrees Celsius.
First, let's gather some information:
- The initial concentration of the solution: 1 gram of PbCl2 in 1.0 liter of water
- The solubility of PbCl2 in water at 25 degrees Celsius: We need to find this information.
To find the solubility of PbCl2 at 25 degrees Celsius, you can refer to a solubility table or use a reliable source such as a chemistry textbook or online database. The solubility of PbCl2 at 25 degrees Celsius is approximately 1.62 grams per liter.
Comparing the initial concentration (1 gram/L) with the solubility (1.62 grams/L), we can see that the initial concentration is less than the solubility. Therefore, when the solution is cooled down to 25 degrees Celsius, some of the PbCl2 will crystallize out.
To calculate how much PbCl2 will crystallize out, we need to find the difference between the initial concentration and the solubility concentration:
1.62 g/L - 1.0 g/L = 0.62 grams
Thus, approximately 0.62 grams of PbCl2 will crystallize out when the solution is cooled to 25 degrees Celsius.
To determine whether some of the PbCl2 will crystallize out when the solution is cooled, you need to calculate the solubility of PbCl2 at 25 degrees Celsius and compare it to the actual concentration in the solution.
To find the solubility of PbCl2 at 25 degrees Celsius, you can consult a solubility table or use a solubility product constant (Ksp) value. The Ksp value represents the equilibrium constant for the dissolution of a solute. For PbCl2, its Ksp value is 1.7 x 10^-5 at 25 degrees Celsius.
Next, convert the given mass of PbCl2 to moles. The molar mass of PbCl2 is approximately 278.1 g/mol, so 1 g of PbCl2 is equivalent to 1/278.1 mol.
Divide the moles of PbCl2 by the volume of the solution to find the initial concentration in mol/L. In this case, the volume of the solution is given as 1.0 L.
Now compare the concentration of PbCl2 in the solution to its solubility. If the concentration is greater than the solubility, crystallization will occur as the solution is cooled.
To calculate how much PbCl2 will crystallize out, subtract the solubility from the initial concentration and multiply it by the volume of the solution. This will give you the mass of PbCl2 that will crystallize out.
Follow these steps, and you should be able to determine whether and how much PbCl2 will crystallize out when the solution cools to 25 degrees Celsius.