the solubility of aluminum sulfate in water at 20 degrees celcius is 26.7 g/100mL

Calculate the molarity?

mols Al2(SO4)3 = grams/molar mass = ?

Then M = mols/L solution.

To calculate the molarity of a solution, you first need to know the molecular weight of the solute (in this case, aluminum sulfate, Al2(SO4)3).

The molecular weight is calculated by adding up the atomic weights of each element in the compound.

For aluminum sulfate (Al2(SO4)3):
- Atomic weight of aluminum (Al) = 26.98 g/mol
- Atomic weight of sulfur (S) = 32.06 g/mol
- Atomic weight of oxygen (O) = 16.00 g/mol

Therefore, the molecular weight of Al2(SO4)3 is:
2(26.98 g/mol of Al) + 3(32.06 g/mol of S) + 12(16.00 g/mol of O) = 342.12 g/mol

Now that we know the molecular weight, we can calculate the molarity using the solubility provided (26.7 g/100 mL).

Molarity (M) is calculated as moles of solute (Al2(SO4)3) divided by volume of solution in liters (L).

First, convert the solubility to moles:
26.7 g Al2(SO4)3 / 342.12 g/mol = 0.078 mol

Next, convert the volume from mL to L:
100 mL / 1000 mL/L = 0.1 L

Finally, divide the moles by the volume in liters:
0.078 mol / 0.1 L = 0.78 M

Therefore, the molarity of aluminum sulfate solution at 20 degrees Celsius is 0.78 M.