Respuesta :

Answer:

1.59 molal

Explanation:

The definition of molality is:

  • molality = moles solute / kg of solvent

So first we calculate the moles of solute (D-glucose, C₆H₁₂O₆), using its molar mass:

  • 36.0 g C₆H₁₂O₆ ÷ 180.156 g/mol = 0.200 mol C₆H₁₂O₆

Then we convert grams of water into kg:

  • 125.9 g H₂O * [tex]\frac{1kg}{1000g}[/tex] = 0.1259 kg H₂O

Finally we calculate the molality:

  • m =  0.200 mol / 0.1259 kg
  • m = 1.59 m