AP Chemistry
9.3 Gibbs Free Energy and Thermodynamic Favorability
9.2 Absolute Entropy and Entropy Change
A materials scientist investigates the thermal desorption of hydrogen from a hypothetical metal hydride according to the following process.
\(\text{MH}_2\text{(s)} \rightarrow \text{M(s)} + \text{H}_2\text{(g)}\)
Assume that \(\Delta H^\circ\) and \(\Delta S^\circ\) do not vary with temperature. What is the temperature threshold, in degrees Celsius, above which the process is thermodynamically favorable under standard-state conditions?
\(\text{MH}_2\text{(s)} \rightarrow \text{M(s)} + \text{H}_2\text{(g)}\)
| Thermodynamic quantity | Value |
|---|---|
| \(\Delta H^\circ\) | \(+75.0\ \text{kJ/mol}\) |
| \(\Delta S^\circ\) | \(+150\ \text{J/(mol·K)}\) |
Assume that \(\Delta H^\circ\) and \(\Delta S^\circ\) do not vary with temperature. What is the temperature threshold, in degrees Celsius, above which the process is thermodynamically favorable under standard-state conditions?
Similar Questions
Tools for a 5
AP aligned mock tests to help you get a 5.
With grading, adaptive explanations, and more.
Find a Quiz
Find, solve, and grade every AP FRQ ever.
Find an FRQ
Stuck on AP Chemistry? Get unstuck with an AP specialist.1 to 1 tutors who know the exam inside out. Understand weeks of material in a single session.Find a Tutor
Learn AP Physics from scratch, quickly. This is the only course you'll need for the year.
A self-paced course with everything you need to get a 5. Trusted by over 15,000 students and 200+ schools. Learn fast, or we'll refund your purchase, backed by our 100% satisfaction guarantee.
Explore the Course