pH, decay, temperature questions

19) The critical temperature of a substance is the a) temperature at which the vapor pressure of liquid is equal to the external pressure b) temperature at which the vapor pressure of the liquid is equal to 760mm Hg. c) temperature at which the solid liquid in vapor phases are in equilibrium d) temperature at which the liquid and vapor phases are in equilibrium at 1 atmosphere e) lowest temperature above which a substance cannot be lquified at any applied pressure 20) If the equilibrium constant for the reaction is 3.7 times 10 to the 15 which of the following correctly describes the standard voltage E^degree symbol, and the standard free energy change, triangleG^degree symbol, f... click for more

Molarity/ chemical equations, shapes

23) ....CrOsub2^- + ... OH^-...CrOsub4^2- + ...Hsub2O+ e^- When the equation for the half reaction above is balanced what is the ratio of the coefficient's OH^-: CrOsub2^-? a) 1:1 b) 2:1 c) 3:1 d) 4:1 e) 5:1 24) CuO(s) + Hsub2(g) <--- / ---> Cu(s) + Hsub2O(g) triangle H = -2.0kJ The Substances in the equation about are at equilibrium at pressure P and temperature T. The Equilibrium can be shifted to favor the products by a) increase the pressure by means of a moving piston at constant T b) increasing the pressure by adding an inert gas such as nitrogen c) decreasing the temperature d) allowing some gases to escape at constant P and T e) adding a catal... click for more

bond length / moles / solution

27) which of the following molecules has the shortest bond length a) N sub 2 b)O sub 2 c)Cl sub 2 d)Br sub 2 e) I sub 2 28) what number of moles of Osub2 his needed to produce 14.2 Grams 0f Psub4Osub10 (molec mass =284g)from P? 29) if 0.060 faraday is passed through an electrolytic cell containing a solution of In^3+ ions, the maximum number of moles of In that could be deposited at the the cathode is

standard heat of formation / acid-base

CHsub4(g) + 2Osub2(g) --> COsub2(g) + 2Hsub2O(l) triangleHsub f^degree symbol Hsub2O(l) =-285.8kJ/mole triangleHsub f^degree symbol COHsub2(g) =-393.3kJ/mole 30) what is the standard heat of formation, triangleHsubf^degree symbol, of methane, CHsub4(g) as calculated from the data above? 31) each of the following can act as both a bronsted acid and a bronsted base except a) HCOsub3^- b) Hsub2POsub4^- c) NHsub4^+ d) Hsub2O e) HS^-

Pi bonding, temperature volume, misc.

32) two flexible containers for gasses are the same temperature and pressure. One holds .50 grams hydrgen and the other 8.0 grams of oxygen. which the following statements regarding these gas samples is false a) the volume of the hydrogen container is the same as the volume of the oxygen container b) the number of molecules in the hydrogen container is the same as the number of molecules in the oxygen container c) the density of the hydrogen sample is less than that of the oxygen sample d) the average kinetic energy of the hydrogen molecules is the same as the average kinetic energy of the oxygen molecules e) the average speed of the hydrogen molecules is the same as the ... click for more