Describe how you would prepare 800ml of .9 M Na3PO4 from solid Na3PO4 and water.
To prepare 800 ml of a 0.9 M Na3PO4 solution, you will need to calculate the amount of solid Na3PO4 required and then dissolve it in water. To do this, follow the steps below:
Step 1: Find the molecular weight of Na3PO4.
The molecular weight of Na3PO4 can be calculated by adding the atomic weights of each element: 3(Na) + (P) + 4(O).
The atomic weights are:
Na = 22.99 g/mol
P = 30.97 g/mol
O = 16.00 g/mol
So, the molecular weight of Na3PO4 = 3(22.99) + 30.97 + 4(16.00) = 163.94 g/mol.
Step 2: Calculate the amount of Na3PO4 needed.
To prepare a 0.9 M solution, you need to know the moles of Na3PO4 required. The formula for moles is moles = Molarity × Volume (in liters).
In this case, the moles of Na3PO4 required are 0.9 moles/L × 0.8 L (since 800 ml is equal to 0.8 L) = 0.72 moles.
Step 3: Convert moles to grams.
To calculate the mass of Na3PO4 required, multiply the moles by the molecular weight:
0.72 moles × 163.94 g/mol = 118.12 g.
So, you would need 118.12 grams of Na3PO4.
Step 4: Dissolve Na3PO4 in water.
Measure out 118.12 grams of solid Na3PO4 using a digital balance. Then, add it to a container. Add some water to aid in the dissolution process, and stir until the solid Na3PO4 is completely dissolved. Finally, add enough water to make a total volume of 800 ml.
Congratulations! You have prepared an 800 ml 0.9 M Na3PO4 solution.