-Los seres vivos empleamos energía para llevar a cabo funciones vitales, como nutrición y respiración.
-En el Sistema Internacional de unidades, la unidad de Energía es el KWh.
-Cuando decimos que la Energía se ha degradado es porque la energía inicial que se transformó en
térmica no puede recuperarse.
-El origen de todas las energías es la materia orgánica.
-La energía eólica, es un tipo de Energía.

Tin has ten stable isotopes. the heaviest, 124sn, makes up 5.80% of naturally occuring tin atoms. how many atoms of 124sn are present in 82.0 g of naturally occurring tin? what is the total mass of the 124sn atoms in this sample?

The climate of the continental united states is generally 1. tropical 2. temperate 3. arctic 4. highland

)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.