Question

Calculate the molality 6.75% solution of ethanol in water​

Answer 1

Answer:

1.574

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