The solubility of calcium sulfate at 30 degrees C is .209 g/100mL solution. Calculate its Ksp i calculated it and got 1.5 x 10 ^-2 but the program said that it was wrong if you could help explain how to do it i would appreciate it
If you had shown your work I could have found the error by now and both of us could move on.
CaSO4 ==> Ca^+2 + SO4^-2
Ksp = (Ca^+2)(SO2^-2)
I looked up the molar mass of CaSO4 and found 136.142 BUT you need to confirm that using values from your text/notes.
0.209 g CaSO4/100 mL = 2.09 g/L
2.09 g/L x (1 mole/136.142 g) = 0.01535 M
Then substitute that number into the Ksp expression I wrote above. The answer I obtained is 2.36E-4
To calculate the solubility product constant (Ksp) for calcium sulfate (CaSO4), you need to determine the concentration of its ions in the saturated solution. The solubility of calcium sulfate is given as 0.209 g/100 mL solution, which can be converted to molar concentration using the molar mass of CaSO4.
Step 1: Convert grams to moles
The molar mass of CaSO4 is:
Ca: 40.08 g/mol
S: 32.06 g/mol
O: 16.00 g/mol (x4)
Therefore, the molar mass of CaSO4 is:
40.08 + 32.06 + (16.00 x 4) = 136.14 g/mol
Using the given solubility, convert grams to moles:
0.209 g * (1 mol/136.14 g) ≈ 0.001534 mol
Step 2: Determine molar concentrations of ions
In calcium sulfate, for every 1 mole of CaSO4 that dissolves, 1 mole of calcium ions (Ca2+) and 1 mole of sulfate ions (SO42-) are produced.
Since the volume is given as 100 mL (0.100 L), the molar concentration of calcium is:
0.001534 mol / 0.100 L = 0.01534 M
And the molar concentration of sulfate is also:
0.001534 mol / 0.100 L = 0.01534 M
Step 3: Calculate Ksp
The solubility product constant (Ksp) expression for calcium sulfate is:
CaSO4(s) ↔ Ca2+(aq) + SO42-(aq)
The Ksp expression is written as:
Ksp = [Ca2+][SO42-]
Substituting the molar concentrations, Ksp = (0.01534)(0.01534)
Simplifying this calculation, Ksp = 0.01534^2
Ksp ≈ 0.000236
Therefore, the calculated Ksp for calcium sulfate at 30°C is approximately 0.000236 or 2.36 x 10^-4.
It seems there might have been an error in your calculation, resulting in a different value for Ksp.
To calculate the solubility product constant (Ksp) of calcium sulfate (CaSO4) at 30 degrees Celsius, you need to know the solubility of the compound in grams per 100 mL of solution. In this case, the solubility of calcium sulfate is given as 0.209 g/100 mL.
To determine Ksp, you need to understand that calcium sulfate dissociates into its ions in water, as shown by the equation:
CaSO4(s) ⇌ Ca2+(aq) + SO42-(aq)
From the balanced equation, you can see that one molecule of CaSO4 produces one Ca2+ ion and one SO42- ion, so their molar solubility will be the same.
Now, we need to convert the given solubility (0.209 g/100 mL) into molar solubility (mol/L). To do this, we'll need the molar mass of CaSO4, which can be calculated by adding the atomic masses.
Molar mass of CaSO4 = atomic mass of Ca + atomic mass of S + 4 × atomic mass of O
Molar mass of CaSO4 = (40.08 g/mol) + (32.06 g/mol) + (4 × 16.00 g/mol)
Molar mass of CaSO4 = 136.14 g/mol
Now, we can calculate the molar solubility (S) of calcium sulfate:
S = (solubility in g/100 mL) ÷ (molar mass of CaSO4)
S = (0.209 g/100 mL) ÷ (136.14 g/mol)
S ≈ 0.001535 mol/L
Since the molar solubility (S) represents the concentrations of Ca2+ and SO42- ions in solution, we can conclude that the Ksp of calcium sulfate at 30 degrees Celsius is:
Ksp = [Ca2+][SO42-] = S^2
Ksp = (0.001535 mol/L)^2
Ksp ≈ 2.36 × 10^-6
Therefore, the correct value for the Ksp of calcium sulfate at 30 degrees Celsius is approximately 2.36 × 10^-6, not 1.5 × 10^-2 as you initially calculated.