35 grams of sodium phosphate are mixed with enough water to make 3.5L of solution having a densityof 1.045g/mol. Find the concentration of sodium phosphate in ppm.
Using the same information, find the molarity of the sodium and phosphate ions.
second part:
moles Na3PO4 = grams/molar mass
M = moles/L soln
first part:
mass soln = 3,500 mL x 1.045 g/mL = about 3657.5 g
(Note: I think you meant to type 1.045 g/mL for the density and not g/mol).
So the solution is 35 g in 3657.5 g
That is 35/3657.5 = about 0.0096 g/g (but you need to do it more accurately). Multiply both numerator an denominator by 1E6 to obtain ppm.
To find the concentration of sodium phosphate in ppm, you first need to calculate the total mass of sodium phosphate in the solution. Then, you can convert this mass into ppm.
Step 1: Calculate the mass of sodium phosphate
Given information:
- Mass of sodium phosphate = 35 grams
- Volume of solution = 3.5 L
- Density of solution = 1.045 g/mL
Since density is given in g/mL, we need to convert volume from L to mL:
Volume of solution = 3.5 L × 1000 mL/L = 3500 mL
To calculate the mass, we can use the formula: mass = density × volume
Mass of sodium phosphate = 1.045 g/mL × 3500 mL = 3657.5 grams
Step 2: Calculate the concentration in ppm
PPM (parts per million) is a unit used to express very small concentrations. It is defined as the ratio of the amount of solute to the amount of solution, multiplied by 1,000,000.
Concentration in PPM = (mass of solute / mass of solution) × 1,000,000
Concentration of sodium phosphate in ppm = (35 grams / 3657.5 grams) × 1,000,000
Concentration of sodium phosphate in ppm = 9560.49 ppm
Therefore, the concentration of sodium phosphate in ppm is approximately 9560.49 ppm.
To find the molarity of the sodium and phosphate ions, we need to know the chemical formula of sodium phosphate. Assuming it is Na3PO4, we can determine the molar mass of the compound and then use the mole ratio to find the molarity.
Step 1: Calculate the molar mass of sodium phosphate (Na3PO4)
The molar mass of sodium (Na) is 22.99 g/mol, and the molar mass of phosphate (PO4) is 94.97 g/mol.
Molar mass of Na3PO4 = (3 × 22.99 g/mol) + (1 × 94.97 g/mol) = 163.94 g/mol
Step 2: Calculate the moles of sodium phosphate
Moles of sodium phosphate = mass of sodium phosphate / molar mass of Na3PO4
Moles of sodium phosphate = 35 grams / 163.94 g/mol = 0.2133 mol
Step 3: Calculate the molarity of the sodium and phosphate ions
Since sodium phosphate dissociates into 3 sodium ions (Na+) and 1 phosphate ion (PO4-), the moles of sodium ions and phosphate ions will be in a 3:1 ratio.
Moles of sodium ions = 0.2133 mol × 3 = 0.6399 mol
Moles of phosphate ions = 0.2133 mol × 1 = 0.2133 mol
The molarity of sodium ions = moles of sodium ions / volume of solution (in L)
Molarity of sodium ions = 0.6399 mol / 3.5 L = 0.1825 M (approximately)
The molarity of phosphate ions = moles of phosphate ions / volume of solution (in L)
Molarity of phosphate ions = 0.2133 mol / 3.5 L = 0.0609 M (approximately)
Therefore, the molarity of the sodium ions is approximately 0.1825 M, and the molarity of the phosphate ions is approximately 0.0609 M.