What would be the molarity of a solution made by dissolving 126g K3PO4 into 1500 mL of water?
M = mol solute/L solution
mols = grams K3PO4/molar mass K3PO4
and L solution = 1.5L
Thank you
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To find the molarity of a solution, you need to know the amount of solute (in moles) and the volume of the solution (in liters). Here's how you can calculate it:
Step 1: Convert the mass of K3PO4 from grams to moles.
To do this, you need to know the molar mass of K3PO4. The molar mass can be calculated by adding up the atomic masses of each element.
Molar mass of K = 39.10 g/mol
Molar mass of P = 30.97 g/mol
Molar mass of O = 16.00 g/mol
Now let's calculate the molar mass of K3PO4:
Molar Mass of K3PO4 = (3 x Molar mass of K) + Molar mass of P + (4 x Molar mass of O)
= (3 x 39.10 g/mol) + 30.97 g/mol + (4 x 16.00 g/mol)
= 164.28 g/mol
Now, we can convert the mass of K3PO4 to moles using the formula:
Number of moles = Mass (g) / Molar mass (g/mol)
Number of moles = 126g / 164.28 g/mol
Number of moles ≈ 0.766 mol
Step 2: Convert the volume of the solution from milliliters to liters.
Since molarity is expressed in terms of liters, we need to convert 1500 mL to liters:
Volume of solution = 1500 mL / 1000 mL/L
Volume of solution = 1.5 L
Step 3: Calculate the molarity of the solution.
Molarity (M) = Number of moles / Volume of solution (in liters)
Molarity = 0.766 mol / 1.5 L
Molarity ≈ 0.5107 M
Therefore, the molarity of the solution made by dissolving 126 g of K3PO4 into 1500 mL of water is approximately 0.5107 M.