Answer:
1.574
Step-by-step explanation:
Given that:
Gram of solution = 100 g
Solution = solute + solvent
Solute = 6.75% = (6.75 / 100) * 100 = 6.75 g (Ethanol) (C2H5OH)
Solvent = 100 - 6.75 = 93.25 g
Recall :
Molality = (mol of solute / kg of solvent)
Mole of solute = gram / molar mass
Molar mass of C2H5OH = (12 * 2) + (1 * 5) + 16 + 1 = 46g/mol
Mole = 6.75g / 46g/mol
Mole = 0.1467391
93.25 g to kg
1000 g = 1 kg
93.25 g = 93.25 / 1000 = 0.09325
Hence,
Molality = 0.1467391 / 0.09325
= 1.5736096
= 1.574