A typical exercise will ask: "Determine the wavelength of the photon emitted during the transition from n=3 to n=1."
When a problem is truly hard—requiring a written justification rather than a calculation—the manual gives up entirely. It writes: "See the course. The law of decay is exponential." That’s it. That is the correction. "See the course." It assumes the student cannot justify why it is exponential; they just have to state that it is. correction manuel physique chimie terminale hatier
Instead, they find this: ΔE = -13.6(1/1² - 1/3²) = -12.09 eV. λ = 103 nm. Wait. Where is the math? How did -12.09 eV become 103 nm? The manual assumes the student knows that you must multiply by (1.6 \times 10^{-19}), divide by Planck's constant, divide by the speed of light, and multiply by (10^9). A typical exercise will ask: "Determine the wavelength