Cálculo da Entalpia Padrão

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160 Chapter 5 5-44. The standard molar enthalpy of formation of CO₂(g) at 298 K is -393.509 Use the following data to calculate the value of at 1000 K. Assume the gases behave ideally under these conditions. = 2.593 + (7.661 X 10⁻³ K⁻¹)T - (4.78 X 10⁻⁶ = 3.094 + (1.561 X 10⁻³ (4.65 X 10⁻⁷ K⁻²)T² = -0.6366 + (7.049 X 10⁻³ - (5.20 X 10⁻⁶ + (1.38 X We can create a figure similar to Figure 5.10 to illustrate this reaction. CO₂(g) C(s) + O₂(g) CO₂(g) Now use Hess's Law to calculate the standard reaction enthalpy at 1000 K: = -393.509 + R 298 1000 - - dT = -393.509 + R [4047.167 K 2732.278 1419.433 = -393.509 0.869 = -394.378 5-45. The value of the standard molar reaction enthalpy for + is -802.2 at 298 K. Using the heat-capacity data in Problems 5-43 and 5-44 in addition to = 2.099 + (7.272 X 10⁻³ + (1.34 X 10⁻⁷ to derive a general equation for the value of at any temperature between 300 K and 1500 K. Plot H° versus T. Assume that the gases behave ideally under these conditions. We can create a figure similar to Figure 5.10 to illustrate this reaction. CH₄(s) + 20₂(g) CH₄(s) +