We want to find the enthalpy change (ΔHΔH) for the reaction: 2CH4->C2H6+H2 Given the following reactions: H2+1/2O2→H2O (Given ΔH=−285.8 kJ CH4→2O2->CO2​+2H2​O (Given ΔH=−890.3 kJ C2H6+7/2O2→2CO2+3H2O (Given ΔH=−1559.9 kJ

The enthalpy change for the oxidation of styrene. C8H8, is measured by calorimetry. C8H8() + 10 O2(g) 8 CO2(g) + 4 H2O() rH = 4395.0 kJ|/mol-rxn Use this value, along with the standard enthalpies of formation of CO2(g) and H2O(), to calculate the enthalpy of formation of styrene. in kJ/mol.

Would the amount of heat absorbed by the dissolution in Example 5.6 appear greater, lesser, or remain the same if the heat capacity of the calorimeter were taken into account? Explain your answer.

The enthalpy of combustion of diamond is -395.4 kJ/mol. C s, dia O2 g CO2 g Determine the fH of C s, dia.

Although the gas used in an oxyacetylene torch (Figure 5.7) is essentially pure acetylene, the heat produced by combustion of one mole of acetylene in such a torch is likely not equal to the enthalpy of combustion of acetylene listed in Table 5.2. Considering the conditions for which the tabulated data are reported, suggest an explanation.

The enthalpy changes of the following reactions can be measured: C2H4(g) + 3 O2(g) 2 CO2(g) + 2 H2O() rH = 1411.1 kJ/mol-rxn Q2H5OH() + 3 O2(g) 2 CO2(g) + 3 H2O() rH = 1367.5 kJ/mol-rxn (a) Use these values and Hesss law to determine the enthalpy change for the reaction C2H4(g) + H2O() C2H5OH() (b) Draw an energy level diagram that shows the relationship between the energy quantities involved in this problem.

One step in the manufacturing of sulfuric acid is the conversion of SO2(g) to SO3(g). The thermochemical equation for this process is SO2(g)+12O2(g)SO3(g)H=98.9kJ The second step combines the SO3 with H2O to make H2SO4. (a) Calculate the enthalpy change that accompanies the reaction to make 1.00 kg SO3(g). (b) Is heat absorbed or released in this process?

A 21.3-mL sample of 0.977 M NaOH is mixed with 29.5 mL of 0.918 M HCl in a coffee-cup calorimeter (see Section 6.6 of your text for a description of a coffee-cup calorimeter). The enthalpy of the reaction, written with the lowest whole-number coefficients, is 55.8 kJ. Both solutions are at 19.6C prior to mixing and reacting. What is the final temperature of the reaction mixture? When solving this problem, assume that no heat is lost from the calorimeter to the surroundings, the density of all solutions is 1.00 g/mL, the specific heat of all solutions is the same as that of water, and volumes are additive.

The enthalpy changes for the following reactions can be measured: CH4(g) + 2 O2(g) CO2(g) + 2 H2O(g) rH = 802.4 kJ/mol-rxn CH3OH(g) + 32 O2(g) CO2(g) + 2 H2O(g) rH = 676 kJ/mol-rxn (a) Use these values and Hesss law to determine the enthalpy change for the reaction CH4(g) + O2(g) CH3OH(g) (b) Draw an energy level diagram that shows the relationship between the energy quantities involved in this problem.

Calculate the enthalpy change when 1.0(1 g of methane is burned in excess oxygen according to the reaction CH,(g) 4- 2O2(g) ->CO2(g) + H-CH/) 1H = -891 kJ/mol