Answer:
3.29 mol/kg
Step-by-step explanation:
To find the molality of the solution, we need to first convert the given mass and volume into moles and kilograms, respectively.
The molar mass of NaCl is 58.44 g/mol, so the number of moles of NaCl in the solution is:
moles of NaCl = 48 g / 58.44 g/mol = 0.8217 mol
The volume of the solution is given as 250 mL, which is equivalent to 0.25 L.
The mass of water in the solution can be calculated from its density, which is 1 g/mL:
mass of water = volume of water x density of water = 0.25 L x 1000 g/L = 250 g
Now we can calculate the molality of the solution as:
molality = moles of solute / mass of solvent in kg
mass of solvent = mass of water / 1000 = 250 g / 1000 = 0.25 kg
Molality = 0.8217 mol / 0.25 kg = 3.29 mol/kg
Therefore, the molality of the solution is 3.29 mol/kg.