Use the example shown to calculate the reaction enthalpy, ΔH, for the following reaction:     CH4(g)+2O2(g)→CO2(g)+2H2O(l) Use the series of reactions that follow: C(s)+2H2(g)→CH4(g), ΔH=−74.8kJ. C(s)+O2(g)→CO2(g), ΔH =−393.5 kJ. 2H2(g)+O2(g)→2H2O(g), ΔH =−484.0kJ. H2O(l)→H2O(g), ΔH =44.0 kJ

The standard enthalpy change for the following reaction is -135 kJ at 298 K. 1/2 N2(g) + 1/2 H2(g) + 3/2 O2(g) HNO3(g)       ΔH° = -135 kJ What is the standard enthalpy change for the reaction at 298 K? N2(g) + H2(g) + 3 O2(g)2 HNO3(g) kJ

A chemist measures the enthalpy change AH during the following reaction: 2 KCl(s) + 302(g) →2 KClO3(s) AH=78. kJ Use this information to complete the table below. Round each of your answers to the nearest kJ. reaction ΔΗ ㅁ x10 2K C103 (s) → 2KC1(s) + 302(g) KCIO, (s)-KCI(s) + 0,(s) 3 KCI(s)+0, (g)KCIO, (s) kJ kJ 1 5

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The enthalpy change for the following reaction is given below. Pb (s) + CO2 (g) → PbO (s) + CO (g) ΔH° = +131.4 kJ Using the standard enthalpies of formation (∆Hf°) of CO2(g) = −393.5 kJ/mol, and CO(g) = −110.5 kJ/mol, determine the standard enthalpy of formation of PbO(s) A. −151.6 kJ ∕ mol B. −283.0 kJ ∕ mol C. +283.0 kJ ∕ mol D. −372.6 kJ ∕ mol E. +252.1 kJ ∕ mol

The balanced thermochemical equation for the combustion of exactly one mole of propane is: C3H8 (g) + 5 O2 (g) → 3 CO2 (g) + 4 H2O(l) ΔH = -2220 kJ/mol What is the enthalpy change for the reaction: 1.5 CO2 (g) + 2 H2O(l)  → 0.5 C3H8 (g) + 2.5 O2 (g) ΔH = ?

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?

Consider the following balanced reaction: 2 H2S(g) + 3 O2(g) → 2 H2O(l) + 2 SO2(g)          ΔHrxn = -1124.0 kJ Calculate the enthalpy of formation (in kJ/mol) for H2S(g). Given: The standard enthalpies of formations (ΔHof) of H2O(l) and SO2(g) are -285.8 kJ/mol and -296.8 kJ/mol, respectively. IMPORTANT: Enter both the sign and the value (no units), using 1 decimal place (e.g. -999.9) Consider the following balanced reaction: 2 H2S(g) + 3 O2(g) → 2 H2O(l) + 2 SO2(g)          ΔHrxn = -1124.0 kJ Calculate the enthalpy of formation (in kJ/mol) for H2S(g). Given: The standard enthalpies of formations (ΔHof) of H2O(l) and SO2(g) are -285.8 kJ/mol and -296.8 kJ/mol, respectively. IMPORTANT: Enter both the sign and the value (no units), using 1 decimal place (e.g. -999.9)

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