What are the five branches of earth science?

Find the empirical formula of each of the following compounds. given mass or for each element in a sample of the compound 3,611 g ca; 6.389 g c1

The difference between the atomic number of an element and the element’s atomic mass is the number of ions.

)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.