Choose the pieces of evidence that supported the existence of pangaea and continental drift theory.
o fossilized plants and animals of the same species found on separate continents.
o geological features, such as mountain ranges, that align on matching coasts of different continents.
o island arc ranges are still connected under the atlantic ocean.
o antarctica's glacial features are similar to the arctic's.

Which of these properties, used alone, would be least useful in identifying most minerals? a. color b. luster c. streak d. density

Which buffer would be better able to hold a steady ph on the addition of strong acid, buffer 1 or buffer 2? explain. buffer 1: a solution containing 0.10 m nh4cl and 1 m nh3. buffer 2: a solution containing 1 m nh4cl and 0.10 m nh3

)benzene and toluene form nearly ideal solutions. consider an equimolar solution of benzene and toluene. at 20 °c the vapour pressures of pure benzene and toluene are 9.9 kpa and 2.9 kpa, respectively. the solution is boiled by reducing the external pressure below the vapour pressure. calculate (i) the pressure when boiling begins, (ii) the composition of each component in the vapour, and (iii) the vapour pressure when only a few drops of liquid remain. assume that the rate of vaporization is low enough for the temperature to remain constant at 20 °c.