A solution prepared by dissolving 42.10g organic compound in 105.4 benzene boils at 84.6C. Determine the...
Calculate the molar mass of naphthalene, the organic compound in mothballs, if a solution prepared by dissolving 7.50 g of naphthalene in exactly 150 g of benzene has a freezing point 2.0°C below that of pure benzene. (Kf of benzene is 5.12°C/m.)
A cyclohexane (c-hex) solution is prepared by fully dissolving 9.11g of a newly synthesized organic compound in 100.g cyclohexane. The freezing point of the solution is depressed by -5.80 oC from the normal freezing point of 6.55 oC for pure cyclohexane ( Kf,c-hex= 20.0 oC kg/mol , MWc-hex = 84.0 g/mol). (a) What is the molecular weight (molar mass) of the organic compound? (b) What is the vapor pressure of the cyclohexane for this solution at 298K?
1. A solution was prepared by dissolving 2.20g of urea (H2NCONH2) in 50.00g of water. If for H2O Tb = 100C, Tf = 0C, Kb = 0.52C / m and Kf = 1.86C / m, determine the freezing and boiling point of the solution. 2. A solution is prepared by dissolving 17.41g of a substance X in 600g of benzene and the resulting solution is frozen at 4.00C. If the freezing point of pure benzene is 5.55C and its Kf...
A solution is prepared by dissolving 16.2 g of benzene (C6H6) in 282 g of carbon tetrachloride (CCl4). The density of the solution is 1.55 g/mL. The molar masses of benzene and carbon tetrachloride are 78.1 g/mol and 154 g/mol respectively. What is the mass percent, mole fraction, molarity and molality of the benzene?
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 prepared at 20 degrees celsius by dissolving 7.44g of an unknown hydrocarbon in 75g benzene (C6H6, 78.112 g/mol, 0.8765 g/cm^3) is found to have a vapor pressure of 376 mmHg at 60 degrees celsius. The vapor pressure of pure benzene at 60 degrees celsius is 400 mmHg. Determine the molar mass of the unknown 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
. 0.275 L of solution is prepared by dissolving 2.50 g of an unknown molecular compound in enough water. The osmotic pressure of this solution is 1.98 atm at 27 °C. (R = 0.08206 L·atm/mol·K) a) Determine the molar mass of the molecular compound. (7 pts) b) If you need to prepare 0.275 L of AlCl3 solution with the same osmotic pressure of the above solution, what mass of AlCl3 (MW = 133.33 g/mol) would you need to weigh out?
A solution was prepared by dissolving 1.846 grams of an unknown compound (nonelectrolyte) in 15.75 grams of water (Kf = 1.86 oC/m). The solution freezes at -1.50 oC. If pure water freezes at 0.00 oC, what's the molar mass of unknown compound?
A solution prepared by dissolving 90.0 mg of a sugar (a molecular compound and a nonelectrolyte) in 1.00 g of water froze at -0.930°C. What is the molar mass of this sugar (g/mol)? The value of Kf is 1.86°C/m.