Question

You perform three different reactions at constant volume and note the heat associated with the three reactions are equal. Reaction 1 produces gas, reaction 2 consumes it and reaction 3 has no gaseous substances as reactants or products. Which statement below is true? Note: Greatest refers to the value, not the magnitude, so -2 is greater than -5 and 1 is greater than both. Select one: a. The internal energy change is greatest for the reaction consuming gas and smallest for the reaction producing gas. b. The internal energy change is greater for the reactions producing and consuming gas than the reaction which does not involve gas. X How much work can be done at constant volume? c. The internal energy change for a reaction is a complicated function and cannot be compared using the information available in this question. d. The internal energy change of the three reactions are equal. e. The internal energy change is greatest for the reaction producing gas and smallest for the reaction consuming gas.

Answer 1

done. W so work = PDV = 0 (is constant voume (V) First law of Thermodynamics. = DU = qtw qto= q ) DU=q three reactions are caval. Given :- Heat 12) with associated to Aut. The internal chana (AU) will be also caval change so The internal energy option (d) This is correct. for all three reactions. - solid < liavid a gas Eniropy (S) Entropy and No. of particles. Temperature increases with seiq e sgas because so option (9) correct is 2 (19) 2 Ale) + Bll) gaseous Product and Here at there is product side, entropy : tas liquid so on DS F S product - S reactant since s product (915) > s reactant Iliavid) so lasso option (d)