A scientist wants to make a solution of tribasic sodium phosphate, , for a laboratory experiment. How many grams of will be needed to produce 400 of a solution that has a concentration of ions of 1.20 ?
CHM 1045, huh?? I'd like to know too!
How many grams of \rm Na_3PO_4 will be needed to produce 450 mL of a solution that has a concentration of \rm Na^+ ions of 1.50 \it M?
To calculate the grams of tribasic sodium phosphate needed to produce a solution with specific concentration, we need to use several pieces of information: the volume of the solution, the desired concentration, and the molar mass of tribasic sodium phosphate.
Step 1: Determine the molar mass of tribasic sodium phosphate (Na3PO4)
The molar mass is calculated by adding up the atomic masses of each element in the compound.
Na (sodium) has a molar mass of 22.99 g/mol
P (phosphorus) has a molar mass of 30.97 g/mol
O (oxygen) has a molar mass of 16.00 g/mol
To calculate the molar mass of Na3PO4, multiply the molar mass of each element by the number of atoms present and add them up:
(22.99 g/mol * 3) + (30.97 g/mol * 1) + (16.00 g/mol * 4) = 163.94 g/mol
Step 2: Calculate the number of moles of tribasic sodium phosphate
To find the number of moles, we can use the equation:
moles = volume (L) * concentration (mol/L)
First, convert the given volume of the solution to liters:
400 mL * (1 L / 1000 mL) = 0.4 L
Now we can substitute the values into the equation:
moles = 0.4 L * 1.20 mol/L = 0.48 mol
Step 3: Convert moles to grams
To convert moles to grams, we need to multiply the number of moles by the molar mass of tribasic sodium phosphate:
grams = moles * molar mass
grams = 0.48 mol * 163.94 g/mol = 78.71 g
Therefore, to produce 400 mL of a solution with a concentration of sodium phosphate ions of 1.20 mol/L, the scientist will need 78.71 grams of tribasic sodium phosphate.