What causes warm air to rise? a. The fact that it's less dense than cold air.
b. The fact that it weighs more than cold air.
c. The fact that it has higher pressure than cold air.
d. The fact that it's more dense than cold air.

What is the subscript for oxygen in its molecular formula

)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.

50 points! need answer asap. what type of organic compound contains the following functional group? (2 points)