Calculate the molality of C₂H₅OH in a water solution that is prepared by mixing 50.0 mL of C₂H₅OH with 100.0 mL of H₂O at 20°C. The density of the C₂H₅OH is 0.789 g/mL at 20°C. A) 1.24 m B) 0.086 m C) 8.56 m D) 0.094 m E) none of these

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To calculate molality, we need the moles of solute (C2H5OH) and the mass of solvent (water) in kg. First, calculate the mass of C2H5OH: 50.0 mL * 0.789 g/mL = 39.45 g. Convert this to moles: 39.45 g / 46.08 g/mol (molar mass of C2H5OH) = 0.856 moles. The mass of water is 100.0 mL * 1.00 g/mL = 100.0 g = 0.100 kg. Molality = moles of solute / kg of solvent = 0.856 moles / 0.100 kg = 8.56 m.

Calculate the Molality of C2H5OH in a Water Solution That

Calculate the Molality of C₂H₅OH in a Water Solution That