For which one of the following is the enthalpy of the reaction the same as the enthalpy of formation? A) H, (g) + F, (g) →2 HF (g) B) Ca (s) + ½ 0, (g) → CaO (s) C) 2 CH,OH (I) + 3 0, (g)2 CO, (g) + 4 H,O(g) D) Sro (s) + CO, (g)→ SrCO, (s)

Given the two thermochemical equations below, find the enthalpy change for the reaction:         N2H4 (l)  +   H2 (g)    →    2 NH3 (g)          delta H =  ?        Given:             N2O4 (g)  +  3 H2 (g)    →     2 NH3 (g)  +  2 O2 (g)      delta H =   – 100.96 kJ             N2O4 (g)  +  2 H2 (g)    →     N2H4 (l)  +  2 O2 (g)        delta H =   + 41.47 kJ Select one: a. – 142.43 kJ b. – 59.49 kJ c. + 41.47 kJ d. + 59.49 kJ e. + 142.43 kJ f. none of these g. – 100.96 kJ

A scientist measures the standard enthalpy change for this reaction to be -739.4 kJ/mol:2CO(g) + 2 NO(g)2CO2(g) + N2(g)Based on this value and the standard formation enthalpies for the other substances, the standard formation enthalpy of CO(g) is

Using the standard enthalpies of formation, what is the standard enthalpy of reaction? CO(g) + H,O(g) –→ CO,(g) + H,(g) AHân = kJ

Use the References to access important values if needed for this question. A scientist measures the standard enthalpy change for the following reaction to be -103.2 kJ: 4HCl(g) + O2(g) → 2H₂O(g) + 2Cl₂ (g) Based on this value and the standard enthalpies of formation for the other substances, the standard enthalpy of formation of HCl(g) is I kJ/mol red Species AH (kJ/mol) H₂O(g) -241.8 Cl₂(g) 0.0 0₂ (9) 0.0

A scientist measures the standard enthalpy change for the following reaction to be -912.5 kJ:2NH3(g) + 3 N2O(g)4N2(g) + 3 H2O(g)Based on this value and the standard enthalpies of formation for the other substances, the standard enthalpy of formation of H2O(g) is  kJ/mol.

（1）Consider the reaction: 2A (g) + 3 B (g) → 2 C (g)     ΔHrxn = +254.3 kJ What will be the enthalpy change (in kJ) if 0.471 mol B reacts in excess A?   （2）Consider the reaction: C (s) + O2 (g) → CO2 (g)     ΔHrxn = -393.5 kJ What mass of carbon (in g) must be reacted via this mechanism to release 581.2 kJ of heat?

A scientist measures the standard enthalpy change for the following reaction to be - 770.6 kJ: 2NO(g) + 2H₂(g) → N₂(g) + 2H₂O (1) Based on this value and the standard enthalpies of formation for the other substances, the standard enthalpy of formation of H₂O(1) is kJ/mol. Substance AH (kJ/mol) NO(g) H₂(g) N₂ (9) 90.3 0.0 0.0