Question
answer part 2 question c.
show all work
eport Graphs and calculations a. Plo t temperature versus time for each set of data. The temperature scale be chosen so that it can be read to one decimal 1. (the y axis) should point of the solution and indicate the value for the freezing point depressi c Calculate the molality of the isopropyl alcohol-acetic acid solution d. From the known weights of solute and solvent, determine the GMW of isopropyl alcoho b. On the graph the graph, clearly label the freezing point of the solvent, the freezing h (The density of glacial acetic acid is 1.05 g/ml) Report the accuracy of your result, expressed as % error e. 2. Answer (Show work for all numerical problems.) Predict which of the following would be the most effective anti-freeze, assumin weights of each are used: methyl alcohol (CH OH); sucrose (C12H22); ethyl alcohol (C2HsOH); ethylene glycol (CH4(OH)2). Explain your choice. a. b. How would you prepare a 1.50 molal solution of sucrose in water? At what temperature c. When 8.40 grams of a non-electrolyte was dissolved in 80.0 grams of water, the solution d. How many grams of ethylene glycol must you add to 10.00 liters of water in your car would the solution begin to boil? froze at -1.52 °C. Calculate the molecular weight of the solute. radiator to protect against freezing at -10.00 °C? To what Fahrenheit temperature does this correspond? solvent: no supercooling solvent: supercooling fp fp time time solution: no supercooling solution: supercooling fp fp time time 20
Explanation / Answer
Tf = 0 - (-1.52 ) = 1.52 °C
Kf = 1.86 °C/m
Tf = Kf x m
m = Tf/Kf = 1.52/1.86 = 0.817 m
mass of solute , w2 = 8.4 g
mass of water, w1 = 80 g = 0.08 kg
molality = no of moles/ mass of solvent
no of moles = 0.817 x 0.08 = 0.06536 mol
no of moles = mass of solute / molar mass
molar mass = mass of solute / no of moles =8.4/ 0.06536 = 128.64 g/mol
