Automative antifreeze is a 60% weight/weight aqueous solution of ethylene glycol (C2H6O2) then its molality is?
Automative antifreeze is a 60% weight/weight aqueous solution of ethylene glycol (C2H6O2) then its molality is?
Explanation
The molar mass of ethylene glycol (C2H6O2) = 2(12.01) + 6(1.01) + 2(16.00) = 62.07 g/mol
Number of moles of ethylene glycol = 60 g / 62.07 g/mol ≈ 0.966 moles
Mass of water = 100 g - 60 g = 40 g
Now, we need to convert the mass of water to kilograms:
Mass of water = 40 g * (1 kg / 1000 g) = 0.04 kg
Now, we can calculate the molality:
Molality (m) = moles of solute / mass of solvent in kg
Molality = 0.966 moles / 0.04 kg ≈ 24.15 moles/kg.