Methanol standard enthalpy

Use the information in Tables 6.3, 6.7, and 6.8 to estimate the enthalpy of formation of each of the following compounds in the liquid state. The standard enthalpy of sublimation of carbon is +717 kJ-moF 1. (a) H20 (b) methanol, CH,OH (c) benzene, C6H6 (without resonance) (d) benzene, C6H6 (with resonance). 

Calculate the standard enthalpy change for the oxidation of methanol to methanal ... 

As noted after equation 4.17, the procedure to evaluate standard enthalpies of formation from appearance energies is somewhat controversial. When the threshold energies are determined from electron impact experiments, it has been argued that the correction terms (H%9S - Hq)a+ + (77298 - o)b - 6.197 in equation 4.17 should not be included in the calculation [66], Consider, for instance, reactions 4.21, and 4.22 where the ion CH2OH+ was produced from the decomposition of 1-propanol or methanol. 

Fig. 23. Standard enthalpy (dashed lines) and Gibbs free-energy (full lines) changes for intermediates in methanol synthesis.

The calibration and application of a heat flux DSC in the study of heterogeneous reactions has been discussed in the literature (248). The possibilities and limitations of this technique were demonstrated for methanation and methanol synthesis on Cu/ZnO catalysts. More recently, Rejai and Gonzalez (222, 223) used a DSC to investigate the reduction of Pt02, PtCl2, and H2PtCl6, the decomposition of calcium oxalate, and the formation of supported Pt-Ru bimetallic catalysts. The results were consistent with values based on standard enthalpies of formation reported in the literature. This work illustrates the power of calorimetry for studying the important processes involved in catalyst preparation and treatment. 

At 298 K. the enthalpy change on combustion of methanol is — 727 kJ mo "l, that of hydrogen is - 286kimoI 1, and that of graphite 394kJmor1. Calculate the standard enthalpy of formation of methanol. 

Methanol (CH3OH) is an organic solvent and is also used as a fuel in some automobile engines. From the following data, calculate the standard enthalpy of formation of methanol ... 

Methanoi (CH3OH) has aiso been proposed as an aiternative fuei. Caicuiate the standard enthalpy of combustion per gram of liquid methanol and compare this answer to that for ethanol in Exercise 87. 

However, we also need to consider how much energy is produced per liter of fuel and how the mass of carbon dioxide produced compares for a given amount of energy produced. Standard enthalpies of combustion given in Appendix 2 are AH/ = -5471 kJ mol for octane and AHj = -726 kJ mol" for methanol. 

Methanol (CH3OH) is used as a fuel in race cars, (a) Write a balanced equation for the combustion of liquid methanol in air. (b) Calculate the standard enthalpy change for the reaction, assuming HjOlg) as a product (c) Calculate the heat produced by combustion per liter of methanol. Methanol has a density of 0.791 g/mL. (d) Calculate the mass of CO2 produced per k) of heat emitted. 

The starting material for polyCphenylene oxide) is 2,6-dimethylphe-nol (2,6-DMP also referred as 2,6-xylenol), which can be obtained by methylation of phenol with methanol, or isolated from coal tars followed by extraction and distillation. The latter process is rarely used nowadays due to the high cost of separation. Currently, only vapor-phase methylation were used for manufacture of o-cresol/2,6-DMP. The alkylation reaction is exothermic, and standard enthalpy change was estimated to be -104kJ/mol for the first methylation (o-cre-sol) and -48kJ/mol for the second methylation (2,6-DMP) as shown... 

The experimental literature value for the standard enthalpy change of combustion of methanol is... 

Hydrogen and methanol have both been proposed as alternatives to hydrocarbon fuels. Write balanced reactions for the complete combustion of hydrogen and methanol and use standard enthalpies of formation to calculate the amount of heat released per kilogram of the fuel. Which fuel contains the most energy in the least mass How does the energy of these fuels compare to that of octane (CgHjg) ... 

The boiling point of methanol is 65.0°C, and the standard enthalpy of formation of methanol vapor is -201.2 kJ/mol. Calculate... 

The standard enthalpy of formation of methanethiol, CH3SH(g), is —22.9 kJ moP. Methanethiol can be synthesized by the reaction of gaseous methanol and H2S(g). Water vapor is another product. Use this information and data from elsewhere in the text to estimate the carbon-to-sulfur bond energy in methanethiol. 

Sfi f-Test 6.13B Methanol is a clean-burning liquid fuel proposed as a replacement for gasoline. Suppose it could be produced by the controlled reaction of the oxygen in air with methane. Find the standard reaction enthalpy for the formation of I mol CHjOH(l) from methane and oxygen, given the following information ... 

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