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 describe an atom as a small, positive nucleus of protons and neutrons surrounded by electrons. (Guide: “What is inside an atom”)
- I can explain why the mass of an atom is almost all in its nucleus. (Guide: “Mass is in the nucleus”; Practice Q6c)
- I can explain that Z identifies the element, A identifies the isotope, and an ion has a nonzero net charge. (Guide: “Elements, isotopes and ions”; Practice Q2, Q6d)
- I can state that the electrons, not the nucleus, mainly decide how an atom interacts with other atoms. (Practice Q6d)
- I can describe the Bohr model as a historical, classical-based model that led to discrete energy states, and say what it cannot do. (Guide: “What the Bohr model can and cannot do”)
Calculation and skills
- I can read nuclear notation and count the protons, neutrons and electrons in an atom or ion. (Guide: Figure 1, Worked example 1; Practice Q1, Q6a)
- I can calculate the net charge of an ion in coulombs. (Guide: Worked example 1; Practice Q6b)
- I can set the Coulomb force equal to mv²/r and find the speed of an electron in an orbit. (Guide: Worked example 2; Practice Q5)
- I can find the electron’s de Broglie wavelength in an orbit and check how many wavelengths fit the circumference. (Guide: Worked example 2; Practice Q5c)
- I can sketch an electron standing wave around an orbit for a given n. (Guide: Figure 2)
Reasoning
- I can explain, using the standing-wave condition 2πr = nλ, why only certain orbits are allowed. (Guide: “Why only some orbits”; Practice Q4)
- I can use functional dependence to compare the radius, speed, force and energy of two orbits. (Guide: Worked example 3; Practice Q3, Q7)
- I can decide whether a proposed orbit is allowed and justify the decision with numbers. (Practice Q7c)
All ticked? Move on to emission and absorption spectra, or return to the course roadmap.