Answer:
Option A) (I) 2.42 m (II) 2.16 M
Explanation:
Let's determine some information.
Solute = CoCl₃ (molar mass = 165.29 g/m); mass of 100 g
Solvent = Water, mass of 250 g
Solution mass = mass of CoCl₃ + mass of water
250 g + 100 g = 350 g of solution
If we want to reach molarity (mol/L), let's determine solution volume with density:
Solution density = solution mass / solution volume
1.25 g/mL = 350 g / solution volume
Solution volume = 350 g / 1.25 g/mL = 280 mL
Let's convert the volume to L → 280 mL = 0.280L
Let's convert the mass of solute to moles = 100 g / 165.29 g/m →0.605 mol
Mol/L = 0.605 moles / 0.280 L = 2.16 M
Now let's calculate molalilty (mol/kg of solvet)
We must convert solvent mass to kg → 250g = 0.250 kg
Then, 0.605 moles / 0.250 kg =2.42 m
