S. Why is it valid to add the enthalpies of any sequence of reactions to obtain...

Transcribed Image Text:

S. Why is it valid to add the enthalpies of any sequence of reactions to obtain the enthalpy of the reaction that is the sum of individual reactions? (a) Because H is a path dependent function (b) Because H is a state function (c) Because H is an extensive variable (d) Because the system is connected to the surroundings 6. True or False: AH for breaking the firstC-H bond in CH, is equal to the average C-H bond enthalpy in this molecule. (a) True (b) False 7. Which of the following statement(s) is/are correct? Breaking bonds are endothermic reactions Adf carbon (diamond) =0 (i) (ii) (iii) The standard reference state of a substance is the most stable state at I bar pressure and 298.15 K There is no temperature dependence to reaction enthalpies (iv) (a) (i) and (ii) (b) (i). (ii) and (ii) (c) (i) and (iii) (d) All of the statements are correct 8. Which of the following equations represents the formation of Fe;O3(s) from its elements in their standard state? (a) Fe;Os(s) → 2Fe(s) + 30(g) (b) 2Fe(s) + 3/20:(g) → Fe:Os(s) (c) Fe(s) + O:(g) → Fe;Os(s) (d) 1/2Fe(s) + 3/20:(g) → Fe:Os(s) 9. True or False: The dependence of reaction enthalpy on temperature is determined by the heat capacities of reactants and products. (a) True (b) False S. Why is it valid to add the enthalpies of any sequence of reactions to obtain the enthalpy of the reaction that is the sum of individual reactions? (a) Because H is a path dependent function (b) Because H is a state function (c) Because H is an extensive variable (d) Because the system is connected to the surroundings 6. True or False: AH for breaking the firstC-H bond in CH, is equal to the average C-H bond enthalpy in this molecule. (a) True (b) False 7. Which of the following statement(s) is/are correct? Breaking bonds are endothermic reactions Adf carbon (diamond) =0 (i) (ii) (iii) The standard reference state of a substance is the most stable state at I bar pressure and 298.15 K There is no temperature dependence to reaction enthalpies (iv) (a) (i) and (ii) (b) (i). (ii) and (ii) (c) (i) and (iii) (d) All of the statements are correct 8. Which of the following equations represents the formation of Fe;O3(s) from its elements in their standard state? (a) Fe;Os(s) → 2Fe(s) + 30(g) (b) 2Fe(s) + 3/20:(g) → Fe:Os(s) (c) Fe(s) + O:(g) → Fe;Os(s) (d) 1/2Fe(s) + 3/20:(g) → Fe:Os(s) 9. True or False: The dependence of reaction enthalpy on temperature is determined by the heat capacities of reactants and products. (a) True (b) False