4. Using phenolphthalein as indicator, 25 mL of a solution containing a mixture of Na2CO3 and KOH requires 15.5 mL of 0.01 M HCl for the endpoint. Addition of
methyPorange indicator to the solution at the phenolphthalein endpoint requires 8.0
mL of the same HCl for the endpoint detection. Calculate the concentration of KOH
in g/l of solution

​

the correct answer is:

a. formation of precipitation

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.