Express each aqueous concentration in the unit indicated. a). 25 mg of trichloroethylene in 9.5 l of water, as ppb of trichloroethylene b). 38 g cl2 in 1.00x 104 l of water, as ppm cl2 c). 2.4 ppm f -, as molarity of fluoride ion, in [mol f - /l] d). 45 ppm no3 -, as molarity of nitrate ion in [mol no3 - /l] e). why do some scientists prefer to express concentrations of water contaminants in the units ppm and ppb rather than molarity

its first and third is your answer i did the qustion the fourth isnt right

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.