Work through the list without notes. If you cannot do a statement, follow its link, then come back. Guide = study guide; Practice = practice questions.
Understanding
- I can explain that absorbing a photon raises the energy of an atom or molecule by exactly the photon’s energy, and emitting one lowers it by that amount. (Guide: “A photon is a fixed packet of energy”)
- I can state whether wavelength, frequency and photon energy are directly or inversely proportional to each other. (Revision notes; Practice Q2)
- I can explain why a brighter lamp delivers more photons but not more energetic ones. (Guide: “Brightness is not photon energy”; Practice Q7)
Calculation
- I can convert a wavelength in cm or nm to metres and use c = λν to find the frequency. (Practice Q1)
- I can use E = hν or E = hc/λ to find the energy of one photon, with units cancelling to J. (Guide: Worked example 1)
- I can convert between energy per photon in J and energy per mole of photons in kJ mol⁻¹. (Practice Q3)
- I can find the longest wavelength able to break a bond from its bond energy. (Practice Q4)
- I can calculate the number of photons, and moles of photons, in a given amount of light energy. (Practice Q6)
Reasoning
- I can use an energy-level diagram to find the wavelength of each emission line and say which region it is in. (Guide: Worked example 2)
- I can work out an unknown energy level from two measured lines, and explain which lines a ground-state atom can absorb. (Practice Q5)
- I can evaluate a claim about light intensity and transitions using calculated photon energies. (Practice Q7)
All ticked? Move on to Topic 3.13, the Beer-Lambert Law, or return to the course roadmap.