Rank the four gases (air, exhaled air, gas produced from the decomposition of h2o2, gas from decomposition of nahco3) in order of decreasing concentration of oxygen).

Describe the interaction that occurs between two objects with the same electrical charge.

Word equation for k(s)+h2o(l) yield koh(aq) + h2(g)

)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.