Question

An ethanol-water solution is 40.00% ethanol by mass and has a density of 0.9450 (g/cm3) at 25.00°C. The density of pure ethanol is 0.7850 (g/cm3) and the density of pure water is 0.9970(g/cm3) at this temperature. At these conditions, the partial molar volume of ethanol is 55.00 (cm3/mol) and the partial molar volume of water is 17.5 (cm3/mol).

a. Calculate the total volume of a 1000.0 g solution assuming both ideal and non-ideal conditions.

b. What does the difference between the volumes calculated in Part a. tell you about the interactions between the water and ethanol molecules in this solution? Explain this difference based on the molecular structure of and electron distribution within these molecules.

Answer 1

Total mass of Ethanol-water mixture 1000 g 401. Ethanol mass : 400g water mass = 600 g Ethanol density = 0.1850 g/cm3 coleter density: 0.9970 glam? Ethanol volone = mass-00g = 509.55mL d 64850 excellen volome EmonsGoogle + 60. 8o and Actuval Total volume of Ilow-to & Till 35 ml partial moker volum of Etoh : 55 partial mokar vokom of H2O = 17.5 (cm3/mol) 04970 mo.ofmoles- weight caleculated Total volume = ve Etimi y = Timo o t TEOH MELON 120 moles Hold moles: 75 ue +55* Se V=17154699 +55 He og V = 583.33 + 418.26 V= 10 61.59 Difference between actual and calecarelle volume : 111-35 - 1061.50 a 49-75 ml. Inta moltitare Breson in solution is different from imba amdecubor force in pure farm. 12