Question detail
Construct a Born-Haber cycle for the formation of sodium chloride (NaCl) from its elements. Include all relevant enthalpy changes.
Try the question, check the answer, then read the explanation to understand the curriculum point.
At a glance
Question
Type
exam_style
Style
Topic
Thermodynamics (A-level only)
Question
Construct a Born-Haber cycle for the formation of sodium chloride (NaCl) from its elements. Include all relevant enthalpy changes.
Answer
The Born-Haber cycle for NaCl includes the following steps: 1) Sublimation of solid sodium (Na) to gaseous sodium (Na(g)), 2) Ionization of Na(g) to Na+(g) and an electron, 3) Dissociation of Cl2(g) to 2Cl(g), 4) Formation of Cl-(g) from Cl(g) by gaining an electron, and 5) Formation of NaCl(s) from Na+(g) and Cl-(g). The enthalpy changes include the enthalpy of sublimation, ionization energy, bond dissociation energy, electron affinity, and lattice enthalpy.
Explanation
This question tests the student's understanding of the Born-Haber cycle and the ability to construct it using enthalpy changes. The answer demonstrates knowledge of the steps involved in the formation of an ionic compound from its elements.
Common mistake
Incorrect Born-Haber Cycle Construction
Students often forget to include all relevant enthalpy changes, such as sublimation and ionization energies, when constructing Born-Haber cycles.
To correctly construct a Born-Haber cycle, include all necessary enthalpy changes: the enthalpy of formation, sublimation, ionization, and electron affinity. For example, use the formula: ΔH_f = ΔH_sublimation + ΔH_ionization + ΔH_electron_affinity + ΔH_lattice. Substitute the values for each enthalpy change, perform the calculations, and ensure all steps are represented in the cycle.
Related flashcards
Flashcard 1 of 5
Related practice questions
Question 1 of 5
Choose an answer, get feedback, then move sideways through the set.