Consider the following enthalpy diagram and enthalpies of intermediate and overall chemical reactions.
which of the following statements is true?
the overall chemical reaction is exothermic.
there are two intermediate reactions in this system.
the third intermediate reaction is endothermic.
the longest arrow represents the overall chemical reaction.

1. suppose a reaction mixture, when diluted with water, afforded 300 ml of an aqueous solution of 30 g of the reaction product malononitrile [ch2(cn)2], which is to be isolated by extraction with ether. the solubility of malononitrile in ether at room temperature is 20.0 g/100 ml, and in water is 13.3 g/100 ml. what weight of malononitrile would be recovered by extraction with (a) three 100-ml portions of ether and (b) one 300-ml portion of ether? suggestion: for each extraction, let x equal the weight extracted into the ether layer. in part (a), the concentration in the ether layer is x/100 and in the water layer is (30 x)/300; the ratio of these quantities is equal to k 20/13.3.

Consider the elements bromine and chlorine; which elements has a larger ionic radius ?

According to coulomb's law, how would the electrical force between particles change if the product of their electrical charge increased?