2.3g of ethanol (C2H5OH) is added to 500g of water to determine the molality of the resulting solution;
Correct answer: B. 0.1 molal
- A. 0.01 molal
- B. 0.1 molal
- C. 1.1 molal
- D. 1.0 molal
Explanation
Mass of ethanol (solute) = 2.3gMass of water (solvent) = 500gFirst, we need to convert the mass of ethanol to moles. The molar mass of ethanol is approximately 46.07 g/molNumber of moles of ethanol = Mas of ethanol / molar mass of ethanolNumber of moles of ethanol = 2.3 / 46.07 = 0.05 molWe need to convert the mass of water to kilograms. So,Mas of water = 500 g = 500 / 1000 = 0.5 kgFinally, we can calculate the molality of the solution:Molality = Number of moles of ethanol/mass of water in kilogramsMolality = 0.05 mol / 0.5kg = 0.1 mol/kgTherefore, the molality of the resulting solution is 0.1 molal.
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