Which fossil is the most effective?
fossil 1- 245-65 mya
fossil 2- 419-240 mya
fossil 3- 551-505 mya
fossil 4- 540-500 mya

Why is an elements atomic mass not listed as a whole number on the periodic table

Identify two types of chemical bonding in the source of dietary potassium

)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.