How do you find the mass of a solution if you have 1L of 2.5 M MgCl2.
I have determined how many moles are present in MgCl2 which was 2.5 and how grams are present which came out to be 238.025g
Now I'm asked "What is the mass of the solution and the mass of the solvent(water)? (Assume the solution has a density of 1.00g/mL)
With a density of 1.00 g/mL, then 1000 mL has a mass of 1.00 g/mL x 1000 mL = 1,000 grams. 238.025 g is MgCl2, 1000-238.025 = mass solvent.
To find the moles of solvent present, would you divide the mass the solvent by 18.02g/mol?
I am given this: MM=18.02g/mol
Sorry the 18.02 is for water.
Yes, moles = grams/molar mass.
Ok now I have to find the mole fraction of the solvent.
I know the formula, which is the moles of a substance/ total moles of solution.
Is the moles of the substance the number we just obtained? And which is the "total" moles of solution?
XMgCl2 = moles MgCl2/(moles MgCl2 + moles H2O)
XH2O = moles H2O/(moles MgCl2 + mols H2O)
To find the mass of the solution, you need to consider both the mass of the solute (MgCl2) and the mass of the solvent (water). Here's how you can calculate it:
1. Find the mass of the solute (MgCl2):
Given that the molar mass of MgCl2 is approximately 95.211 g/mol, and you have determined that there are 2.5 moles of MgCl2 present, you can multiply the molar mass by the number of moles:
mass of MgCl2 = 2.5 moles * 95.211 g/mol
2. Find the mass of the solvent (water):
You're given that the volume of the solution is 1 L and that the density of the solution is 1.00 g/mL. Since density = mass/volume, you can rearrange the equation to solve for the mass:
mass of solvent = volume of solution * density
mass of solvent = 1 L * 1.00 g/mL
3. Find the mass of the solution:
The total mass of the solution is the sum of the masses of the solute and solvent:
mass of solution = mass of solute + mass of solvent
By following these steps, you should be able to calculate the mass of the solution and the mass of the solvent.