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 575mL of a solution that has a concentration of Na^+ ions of 1.40 M?
Answer: mass of Na3PO4 = _____
How is this question started/worked?
Well, one gets three ions of sodium per molecule, so you want a Molarity of the salt of 1.40*3M
Molarity=moles solute/volume
= gramssolute/(molmass*volume)
solve for grams of solute you need use, then make up the volume desired with water.
Oppps. One wants TSP to be 1/3 the concnetration, not three times. ARRRGGGHHH.
Molarity= 1/3 * 1.40 M for the sodium triphosphate.
43.9
To solve this question, we need to use the concept of molarity and the balanced chemical equation of tribasic sodium phosphate, Na3PO4.
The molarity (M) of a solution is defined as the number of moles of solute (in this case, Na^+ ions) per liter of solution. We are given that the concentration of Na^+ ions is 1.40 M, which means there are 1.40 moles of Na^+ ions in every liter of the solution.
Next, we need to calculate the number of moles of Na3PO4 required to produce the solution. According to the balanced chemical equation for Na3PO4, the ratio of Na^+ ions to Na3PO4 is 3:1. This means that 1 mole of Na3PO4 will produce 3 moles of Na^+ ions.
To find the number of moles of Na3PO4, we can use the equation:
moles of Na3PO4 = moles of Na^+ ions / (ratio of Na^+ ions to Na3PO4)
moles of Na3PO4 = 1.40 mol / 3
Now, we can calculate the mass of Na3PO4 needed by multiplying the number of moles of Na3PO4 by its molar mass. The molar mass of Na3PO4 can be calculated by summing the atomic masses of its constituent elements:
molar mass of Na3PO4 = (3 * atomic mass of Na) + atomic mass of P + (4 * atomic mass of O)
Now, you can look up the atomic masses of Na, P, and O from the periodic table and substitute them into the equation to calculate the molar mass of Na3PO4.
Finally, to find the mass of Na3PO4 needed for the solution, multiply the number of moles of Na3PO4 by its molar mass. Remember to convert the volume of the solution from mL to L by dividing it by 1000.
mass of Na3PO4 = moles of Na3PO4 * molar mass of Na3PO4
mass of Na3PO4 = (moles of Na^+ ions / (ratio of Na^+ ions to Na3PO4)) * molar mass of Na3PO4
Solve this equation and you will get the mass of Na3PO4 needed to produce the desired solution.