Bond Enthalpies help needed. For the reaction below: a. Estimate the gas phase e
ID: 920146 • Letter: B
Question
Bond Enthalpies help needed.
For the reaction below:
a. Estimate the gas phase enthalpy change using bond dissociation enthalpies from the OWL Table Reference, not data from your text. Click the References button and then click the Tables link on the drop-down that appears. Include algebraic sign and units.
b. Is the reaction exothermic or endothermic?
c. Is the reaction likely to proceed spontaneously in the direction written?
2.
a. Estimate the gas phase enthalpy change using bond dissociation enthalpies from the OWL Table Reference, not data from your text. Click the References button and then click the Tables link on the drop-down that appears. Include algebraic sign and units.
b. Is the reaction exothermic or endothermic?
c. Is the reaction likely to proceed spontaneously in the direction written?
3.
a. Estimate the gas phase enthalpy change using bond dissociation enthalpies from the OWL Table Reference, not data from your text. Click the References button and then click the Tables link on the drop-down that appears. Include algebraic sign and units.
b. Is the reaction exothermic or endothermic?
c. Is the reaction likely to proceed spontaneously in the direction written?
Explanation / Answer
1.
a. Given reaction,
enthalpy change dHrxn = dH(reactants) - dH(products)
= 85 - 103
= -18 kcal
b. The reaction is exothermic, sign of enthalpy change is -ve.
c. The reaction will proceed spontaneously as written.
2.
a. For the given reaction,
dHrxn = (99+35) - (101+111)
= -80 kcal
Since the sign of enthalpy change for the reaction is -ve, the reaction will proceed spontaneusly as written towards the products.
b. The reaction is exothermic
c. The reaction will be spontaneous as written
3.
a. Enthalpy change dHrxn = 58-103 = -45 kcal
b. The reaction is exothermic
c. The reaction will proceed as written spontaneously