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VICChemistryQuick questions
Unit 1: How can the diversity of materials be explained?
Quick questions on Electron configurations and periodic trends: VCE Chemistry Unit 1
10short Q&A pairs drawn directly from our worked dot-point answer. For full context and worked exam questions, read the parent dot-point page.
What is shells, subshells, orbitals?Show answer
The Schrödinger model places electrons in regions called orbitals, grouped into subshells, grouped into shells.
What is filling order (aufbau)?Show answer
Subshells fill from lowest energy upward. For neutral atoms up to Z = 36 the order is:
What is spdf notation?Show answer
Write the subshells in order with the number of electrons as a superscript. The exponents must sum to the total number of electrons. Examples up to Z = 36:
What is ions?Show answer
For anions, add electrons to the next available orbital. O (1s^2 2s^2 2p^4) gains two electrons to become O^2- (1s^2 2s^2 2p^6).
What is periodic trends?Show answer
Three factors explain almost every trend:
What is writing 3d before 4s in a neutral atom?Show answer
Filling order for neutral atoms is 4s before 3d. (Order in cations is the reverse.)
What is removing 3d electrons first when ionising a transition metal?Show answer
Always remove the 4s electrons first.
What is forgetting Cr and Cu are anomalies?Show answer
Both promote one 4s electron into 3d for extra stability.
What is saying nuclear charge instead of core charge?Show answer
Nuclear charge is the full +Z. Core charge is what's left after the inner shells shield it. Use the latter when explaining periodic trends.
What is mixing radius and ionisation energy trends?Show answer
They go in opposite directions (radius and ionisation energy are inversely related across both periods and groups).