A calcium iodide solution is made by mixing 0.520g of calcium iodide with 12.0ml of water.
1) Determine the moles of calcium iodide used to make the solution
2) Determine the mass of solvent used to make the solution. Assume that the density of water is 1.000g/ml.
3) Determine the molality of calcium iodide of the solution.
4) Determine the molality of all solutes of the solution.
1. mols CaI2 = grams/molar mass = ?
2. mass - volume x density = 12.0 mL x 1.000 g/mL = ?
3.m = mols/kg solvent
4. I'm confused about the term "molality of all solutes). I assume you want the m of Ca ion and m of I ion.
m Ca^+ is the same as m CaI2.
m I^- is 2x m CaI2.
Please check if am i got it right
1. mols Cal2 = 0.520g/293.886 = 0.001769g/mol
2. Mass-volume x density
= 12.0ml x 1.00g/ml = 12g/ml
3. M= mols/kg solvant
how do I get kg solvent.
is this right 0.001769/12 to get the ans = 1.47417E-4
4, it says determine the molality of all solutes means all actions and anions. How do I calculate this.
To answer these questions, we need to use the molar mass and density of calcium iodide and water. Here is how you can calculate each value:
1) Determine the moles of calcium iodide used to make the solution:
The molar mass of calcium iodide (CaI2) can be calculated by adding the atomic masses of calcium (Ca) and iodine (I).
Molar mass of Ca = 40.08 g/mol
Molar mass of I = 126.9 g/mol
Molar mass of CaI2 = (2 * molar mass of I) + molar mass of Ca = (2 * 126.9 g/mol) + 40.08 g/mol = 293.88 g/mol
Now, we can calculate the moles of calcium iodide used by dividing the given mass by the molar mass.
Moles of calcium iodide = Mass of calcium iodide / Molar mass of calcium iodide
= 0.520 g / 293.88 g/mol
≈ 0.001769 mol (rounded to 4 decimal places)
2) Determine the mass of solvent used to make the solution:
The density of water is given as 1.000 g/ml, and the volume of water used is 12.0 ml.
Mass of solvent = Volume of water × Density of water
= 12.0 ml × 1.000 g/ml
= 12.0 g
So the mass of solvent used to make the solution is 12.0 g.
3) Determine the molality of calcium iodide in the solution:
Molality is defined as the number of moles of solute per kilogram of solvent.
Molality (m) = Moles of solute / Mass of solvent (in kg)
The mass of solvent was determined to be 12.0 g in the previous step. To convert it to kilograms, divide by 1000.
Mass of solvent (in kg) = 12.0 g / 1000
= 0.012 kg
Now, we can calculate the molality of calcium iodide by dividing the moles of calcium iodide by the mass of solvent in kilograms.
Molality of calcium iodide = Moles of calcium iodide / Mass of solvent (in kg)
= 0.001769 mol / 0.012 kg
≈ 0.1474 mol/kg (rounded to 4 decimal places)
So, the molality of calcium iodide in the solution is approximately 0.1474 mol/kg.
4) Determine the molality of all solutes in the solution:
Since calcium iodide is the only solute in the solution, the molality of all solutes will also be the same as the molality of calcium iodide. Thus, the molality of all solutes is approximately 0.1474 mol/kg.