A scientist wants to make a solution of tribasic sodium phosphate, Na3PO4, for a laboratory experiment. How many grams of Na3PO4 will be needed to produce 500 mL of a solution that has a concentration of Na+ ions of 0.700 M
You want 0.700M in Na^+ which means 1/3 of that for Na3PO4 or 0.700/3 = ??
How many moles do you want? That will be ??M x L = xx moles.
How many grams is that.
moles = grams/molar mass.
To calculate the grams of Na3PO4 needed to make the solution, we need to know the molar mass of Na3PO4 and the volume of the solution.
1. Molar mass of Na3PO4:
- Na (sodium) has a molar mass of 22.99 g/mol (from the periodic table)
- P (phosphorus) has a molar mass of 30.97 g/mol (from the periodic table)
- O (oxygen) has a molar mass of 16.00 g/mol (from the periodic table)
Adding up the molar masses, we get:
Molar mass of Na3PO4 = (3 * Na) + P + (4 * O)
Molar mass of Na3PO4 = (3 * 22.99) + 30.97 + (4 * 16.00)
Molar mass of Na3PO4 = 163.94 g/mol
2. Concentration of Na+ ions:
The concentration, C (in moles per liter), is given as 0.700 M, which means there are 0.700 moles of Na+ ions in 1 liter of the solution.
3. Volume of the solution:
The volume, V (in liters), is given as 500 mL. To convert mL to liters, divide by 1000:
V = 500 mL / 1000 = 0.500 L
Now, we can calculate the amount of Na3PO4 needed:
Amount of Na3PO4 (in moles) = Concentration (in moles per liter) * Volume (in liters)
Amount of Na3PO4 = 0.700 * 0.500
Finally, to calculate the grams of Na3PO4 needed, we can use the molar mass:
Grams of Na3PO4 = Amount of Na3PO4 (in moles) * Molar mass of Na3PO4
Grams of Na3PO4 = (0.700 * 0.500) * 163.94
Evaluate the expression to find the answer.