Ch.18 - Thermodynamics: Entropy, Free Energy & Equilibrium

McMurry8th EditionChemistryISBN: 9781292336145Non è quello che usi tu?Cambia libro di testo

McMurry 8th Edition

Ch.18 - Thermodynamics: Entropy, Free Energy & Equilibrium

Problema 126a

Capitolo 18, Problema 126a

Trouton's rule says that the ratio of the molar heat of vaporization of a liquid to its normal boiling point (in kelvin) is approximately the same for all liquids: ∆H_vap/T_bp ≈ 88 J/(K*mol) (a) Check the reliability of Trouton's rule for the liquids listed in the following table.

Guida verificata passo dopo passo

Trouton's rule states that the ratio of the molar heat of vaporization (\( \Delta H_{\text{vap}} \)) to the normal boiling point in Kelvin (\( T_{\text{bp}} \)) is approximately 88 J/(K*mol) for many liquids.

Collect the molar heat of vaporization (\( \Delta H_{\text{vap}} \)) and the normal boiling point (\( T_{\text{bp}} \)) in Kelvin for each liquid from the provided table.

For each liquid, calculate the ratio \( \frac{\Delta H_{\text{vap}}}{T_{\text{bp}}} \) using the values obtained from the table.

Compare the calculated ratio for each liquid to the value of 88 J/(K*mol) as predicted by Trouton's rule.

Determine if the calculated ratios are close to 88 J/(K*mol) and discuss any deviations, considering factors such as molecular complexity or hydrogen bonding that might affect the reliability of Trouton's rule.>

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.

Durata del video:

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Trouton's Rule

Trouton's Rule states that the ratio of the molar heat of vaporization (∆H<sub>vap</sub>) of a liquid to its boiling point (T<sub>bp</sub> in Kelvin) is approximately constant for many liquids, typically around 88 J/(K·mol). This empirical rule helps predict the vaporization behavior of liquids and is particularly useful in thermodynamics and physical chemistry.

Video consigliato:

Percorso guidato

00:28

Solubility Rules

Molar Heat of Vaporization

The molar heat of vaporization is the amount of energy required to convert one mole of a liquid into vapor at its boiling point, under constant pressure. It is a crucial thermodynamic property that reflects the strength of intermolecular forces in a liquid; higher values indicate stronger forces and greater energy needed for vaporization.

Video consigliato:

Percorso guidato

02:19

Heat Capacity

Normal Boiling Point

The normal boiling point of a liquid is the temperature at which its vapor pressure equals the atmospheric pressure (1 atm). It is a key characteristic of a substance, influencing its phase transitions and is essential for applying Trouton's Rule, as the boiling point must be expressed in Kelvin for accurate calculations.

Video consigliato:

Percorso guidato

03:05

Boiling Point Elevation

Pratica correlata

Domanda del libro di testo

Consider the Haber synthesis of gaseous NH₃ (∆H°_f = -46.1 kJ/mol; ∆G°_f = -16.5 kJ/mol: (d) What are the equilibrium constants K_p and K_c for the reaction at 350 K? Assume that ∆H° and ∆S° are independent of temperature.

490

views

Domanda del libro di testo

Is it possible for a reaction to be nonspontaneous yet exo-thermic? Explain.

242

views

Domanda del libro di testo

Trouton's rule says that the ratio of the molar heat of vaporization of a liquid to its normal boiling point (in kelvin) is approximately the same for all liquids: ∆H_vap/T_bp ≈ 88 J/(K*mol) (b) Explain why liquids tend to have the same value of ∆Hvap/Tbp.

808

views

Domanda del libro di testo

Tell whether reactions with the following values of ΔH and ΔS are spontaneous or nonspontaneous and whether they are exothermic or endothermic. (a) ΔH = - 48 kJ; ΔS = + 135 J>K at 400 K (b) ΔH = - 48 kJ; ΔS = - 135 J>K at 400 K (c) ΔH = + 48 kJ; ΔS = + 135 J>K at 400 K (d) ΔH = + 48 kJ; ΔS = - 135 J>K at 400 K

520

views

Domanda del libro di testo

Use the data in Appendix B to calculate the equilibrium pressure of CO₂ in a closed 1 L vessel that contains each of the following samples:

(a) 15 g of MgCO₃ and 1.0 g of MgO at 25 °C

(b) 15 g of MgCO3 and 1.0 g of MgO at 280 °C .

Assume that ∆H° and ∆S° are independent of temperature.

308