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 why chemists need the mole to connect a mass measured on a balance to a number of particles. (Guide: “Why chemists count in moles”; Practice Q7)
- I can state Avogadro’s number with its unit, N_A = 6.022 × 10²³ mol⁻¹. (Guide)
- I can explain why the molar mass in g mol⁻¹ has the same number as the average particle mass in amu. (Guide: “Molar mass”; Practice Q7)
- I can say what “particle” means for an element, a molecular compound and an ionic compound. (Guide)
Calculation
- I can calculate the molar mass of a formula that contains brackets, such as Ca(NO₃)₂. (Practice Q1)
- I can convert a mass into moles and a number of particles, writing units at every step. (Guide: Worked example 1)
- I can count the atoms of one element in a given amount of a compound. (Practice Q4)
- I can work backwards from a number of atoms to the mass of the sample. (Guide: Worked example 2)
- I can find the mass of a single atom or molecule, and use it to identify a substance. (Practice Q3, Q5)
- I can give a final answer with the correct number of significant figures. (All worked examples)
Reasoning
- I can compare the numbers of particles in samples of different substances without assuming equal mass means equal particles. (Practice Q2, Q6)
- I can state an assumption behind a mole calculation, such as sample purity or natural isotope abundance. (Practice Q7; Revision notes)
All ticked? Move on to Topic 1.2, Mass Spectra of Elements, or return to the course roadmap.