What is the molarity of a solution prepared by dissolving 820. g of sodium phosphate, Na3PO4, in water and diluting to 2.89 liters?

(atomic masses: Na = 22.99, P = 30.97, O = 16.00)

How many mols do you have? That's mols = grams/molar mass = ?

Then M = mols/L solution (which is 2.89L)

To find the molarity of the solution, we need to calculate the number of moles of sodium phosphate and then divide it by the volume of the solution in liters.

Step 1: Calculate the number of moles of sodium phosphate (Na3PO4).
The molar mass of Na3PO4 can be calculated by multiplying the atomic mass of each element by the number of atoms present in the compound:
Na: 3 * 22.99 = 68.97 g/mol
P: 1 * 30.97 = 30.97 g/mol
O: 4 * 16.00 = 64.00 g/mol
Total molar mass: 68.97 + 30.97 + 64.00 = 163.94 g/mol

To find the number of moles, divide the mass of the compound (in grams) by its molar mass:
Number of moles = Mass / Molar mass
Number of moles = 820 g / 163.94 g/mol

Step 2: Calculate the volume of the solution in liters.
The volume of the solution is given as 2.89 liters.

Step 3: Calculate the molarity.
The molarity is defined as the number of moles of solute divided by the volume of the solution in liters:
Molarity (M) = Number of moles / Volume (in liters)

Now, you can substitute the values into the equation to find the molarity of the solution:
Molarity = (820 g / 163.94 g/mol) / 2.89 L

By calculating this expression, you will find the molarity of the solution.