Blog

@X@user.full_name@X@ @GMU: Determine the molality of a 6.932 wt % aqueous solution of LiCl.

@X@user.full_name@X@   @GMU: To what temperature would the reaction below need to be heated to have a rate constant of 6.09e-4 M-1s-1 if the rate constant was 2.700e-4 M-1s-1 at 327.00°C and the activation energy was 166.00 kJ/mol?H2(g) + I2(g) → 2HI(g)

@X@user.full_name@X@ @GMU: When 10.93 g of citric acid was dissolved in 105.9 g of benzene, the freezing point was 275.9 K. What is the formula mass of this compound? The freezing point depression constant for benzene is 5.12 (°C*kg)/mol. The melting point and boiling points are 5.50°C and 80.10°C, respectively.

John Schreifels @GMU: What is the change in mass of 71Ga when it is formed from protons, electrons and neutrons if the atom has a mass of 70.9247005 amu? The masses of the proton, electron and neutron are 1.00728 amu, 0.000549 amu and 1.00867 amu, respectively.

@X@user.full_name@X@ @GMU: How much time in minutes would it take for a 1.9957 g sample of 33P to decay to a mass of 1.1357 g if it has a half-life of 2.160e6 s.

@X@user.full_name@X@ @GMU: Which of the crystalline substances below is an example of a ionic solid?

@X@user.full_name@X@ @GMU: The vapor pressure of benzene, C6H6, (l) at 314.9 K is 212.1 mm Hg. What is the heat of vaporization if its normal boiling point is 353.3 K?

@X@user.full_name@X@ @GMU: By how much would the rate of reaction (see below) change if the concentration of Cl2 increased by a factor of 1.981. The rate law of this reaction is Rate = k[CHCl3][Cl2]1/2.CHCl3(g) + Cl2(g) → CCl4(g) + HCl(g)

@X@user.full_name@X@ @GMU: When 0.1728 g of lysine was dissolved in 107.9 mL of water, the osmotic pressure at 33.71°C was 0.2762 atm. What is the formula mass of this compound?

@X@user.full_name@X@ @GMU: What is the pOH of a 0.1203 M H2CO3 ? See reaction belowH2CO3 + H2O → HCO-3 + H3O+ Ka = 4.300×10-7