A solution made by dissolving 150.0 g of an unknown compound in 425.0 mL of benzene to make a solution which has a freezing point 18.6 °C lower than that of pure benzene. Kf for benzene is 5.12 °C/m and the density of benzene is 0.877 g/mL.
b) The molality of the solution is 3.63. How many moles of the unknown compound were dissolved in the solution?
C) what is the molar mass of the unknown compound?
A solution made by dissolving 150.0 g of an unknown compound in 425.0 mL of benzene...
The molar mass of unknown molecular compound is determined using freezing point depression. The substance is dissolved in benzene (C6H), an organic solvent. Use the data below to determine the molar mass of the substance. 8.65 g Mass of unknown compound Freezing point of solution Volume of benzene -10.21°C 35.0 mL 5.53°C Freezing point of benzene Density of benzene Kf for benzene 0.8765 g/mL 5.12°C/m Molar mass = g/mol
When 12.6-grams of an unknown compound is placed in 0.116-kg of benzene, the freezing point is changed by 2.34°C. The value of Kf= 4.90°C/m for benzene. Determine the molar mass of the unknown compound. Answer to 1 decimal place and include your units. Answer: Determine the molality of a solution when 32.3 grams of ethanol, C2H5OH (Molar mass = 46.08 g/mol) is dissolved in 0.947 kg of water. Answer to 2 decimal places. Answer: Find the freezing point of a...
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...
A solution made by dissolving 85.0 g f sucrose (Molar mass. 342.3 g/mol) in 515 go acetic acid at 25 degree C froze at 14.95degreeC. Freezing point of the pure acetic acid is 16.90degreeC.Density of acetic acid is 1.05 g/ml. at 25 degree C. Answer the following and show your work in the space provided. Molality of sucrose solution = K_i of acetic acid = 93.42 g of an unknown non-volatile, non-electrolyte solute was dissolved in 850.g of acetic acid....
A student made a solution by dissolving 0.144g of an unknown in 10.00g of benzene, C6H6, and found the vapor pressure solution to be 94.35mm Hg. The vapor pressure of pure benzene is 95.00mm Hg at the temperature of the experiment. (Show your work and use the factor labor method) a. what is the mole fraction of benzene in the solution? b. how many moles of benzene were in the solution? c. how many moles of unknown were in the...
The freezing point of a solution of 1.104 g of an unknown nonelectrolyte dissolved in 36.81 g of benzene is 1.08°C. Pure benzene freezes at 5.48°C and its Kf value is 5.12°C/m. What is the molecular weight of the compound?
2. A solution of an unknown molecular substance is prepared by dissolving 0.50 g of the unknown in 8.0 g of benzene. The solution freezes at 3.9°C. Determine the molar mass of the unknown. (Benzene has a freezing point of 5.5°C and a Kfvalue of 5.12°C/m) 10
3. The density of a 4.53 M NH, solution is 0.9651 g/mL Calculate the molality 4. Calculate the freezing and boiling points of a solution made by mixing 10.5 g magnesium iodide with 150.0 g water. 5. A solution prepared by dissolving 0.56 g of a non-ionic solute in 25.0 g benzene freezes at 4.45°C. What is the molar mass of the solute?
The freezing point of a solution that contains 1.00 g of an unknown compound, (A), dissolved in 10.0 g of benzene is found to be 2.17 oC. The freezing point of pure benzene is 5.48 oC. The molal freezing point depression constant of benzene is 5.12 oC/molal. What is the molecular weight of the unknown compound?
What is the freezing point (in K) of a solution made by dissolving 19.831g of CCl4 in 130.0 g of benzene? Pure benzene has a freezing point of 5.5°C and a Kf = 5.12 °C/m. Write your answer in Kelvin with 4 sig figs!