% Error = [ Exp MM- True MM]*100/True MM
The true mass of glucose is 180.156 g/mol. The molar mass of glucose was found experimentally...
מו Calculate the mass of glucose (C6H606) that must be added to 100 g of water to give a solution whose freezing point is -3.8°C. The freezing point depression constant of water is 1.86 °C/m. The molar mass of glucose is 180.16 g/mol Give your answer in grams to 3 significant figures
1.A solution that contains 15.581 grams of benzene (molar mass = 78.1 g/mol) in 420 g of cyclohexane freezes at a temperature 9.50 ºC below the freezing point of pure cyclohexane. Calculate the molar freezing point depression constant, Kf, for cyclohexane. 2. The molar boiling point elevation constant for water is 0.512 ºC/m. What is the boiling point of a solution containing 673 g of water and 78.0 g of CaCl2? 3. A solution containing 32.0 g of an unknown...
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question 1 the molar mass of unknown is 102g/mol
hation by Freezing Point Depression Vernier Logger Pro for Windows Section Post-Laboratory Questions (Use the space provided and additional paper if necessary. Record your nemerical answers in the boxes provided.) 1. Obtain the correct molar mass of your unknown from your laboratory instructor. Calculate the percent error in the molar mass that you found. Torg/mol percent error, 2. A student determined the freezing point of pure t-butyl alcohol following the...
Pure benzene, C6H6, has a molar mass of 78.114 g mol-1, a density of 0.8765 g mL-1, a freezing point of 5.45°C, and a boiling point of 80.2°C. Its freezing point depression and boiling point elevation constants are: Kf = 5.07°C m-1; Kb = 2.53oC m-1. A solution was made by taking 33.88 g of an unknown nonelectrolyte and dissolving it in 175.0 g of benzene. The measured freezing point of the solution was 1.65oC. Calculate the molar mass of...
The molar mass of a compound expresses the ratio of mass to moles Part A molar mass- _mass in gr tert-Butyl alcohol is a solvent with a Kf of 9.10 °C/m and a freezing point of 25.5 °C. When 0.807 g of an unknown colorless liquid was dissolved in 11.6 g of tert-butyl alcohol, the solution froze at 15.3°C number of moles This quantity can be determined experimentally by accurately measuring the mass of the sample and determining the corresponding...
A student is determining the molar mass of an unknown compound based on the following data: mass compound: 4.80 g mass solvent (water): 0.022 kg new freezing point: -2.50 oC freezing point depression constant (Kf): 1.86 oC/molal (Freezing point of pure water = 0 oC) 0.0786 g/mol 162.33 g/mol 0.00616 g/mol 293.26 g/mol
3a. Calculate the molar mass (in g/mol) of an unknown 1:1 electrolyte if 0.482 g dissolved in 223.1 mL of water at 74.75 °C has an osmotic pressure of 54.4 mmHg. R = 0.082058 L⋅atm⋅mol−1⋅K−1. 1.00 atm = 760 mmHg. Report your answer to THREE significant figures. 3b. Calculate the required mass of an unknown nonelectrolyte (ℳ = 131.5599 g/mol) dissolved in 140.1 g of solvent that gives a solution that boils at 36.04 °C. The boiling point of the...
Post-Lab Material Experiment 19 Data and Calculations: Molar Mass Determination by Depression of the Freezing Point 0.3 Name Section A. Measured Freezing Point of Pure Water B. Finding the Freezing Point of a Solution of Liquid Unknown Target mass of solute (Calculated based on the parameters in the instructions) Unknown # Liquid 3.5 Actual mass of solute used Trial Freezing point of solution (observed) -3.0 Mass of solution 116.6 Trial II Freezing point of solution -3.3 Mass of solution 101.3....
7. The vapor pressure of water at 25.0°C is 23.8 torr. Determine the mass of glucose (molar mass = 180 g/mol) needed to add to 500.0 g of water to change the vapor pressure to 23.3 torr. (20 points) Thyroxine, an important hormone that controls the rate of metabolism in the body, can be isolated from the thyroid gland. If 0.455 g of thyroxine is dissolved in 10.0 g of benzene, the freezing point of the solution is found to...
Freezing point depression can be used to experimentally determine the van't Hoff factor of a solute in solution. Given the data in the table, please answer the questions below and determine the "real" van't Hoff factor of the solute. Experimental Results Mass of solvent (water) Freezing point of water Freezing point depression constant (Kf) of water Mass of solution Freezing point of solution 8.515 g 0.00°C 1.86°C/m 9.3589 -5.45°C a. What mass of solute was used? b. What is the...