Trend in atomic radius across period 3?
Answer: Decreases
Colour of aqueous potassium iodide after chlorine water is added?
Answer: Brown
Amphoteric period 3 oxide?
Answer: Al₂O₃
IB Chemistry · Structure 3
IB Chemistry Structure 3: Classification of matter
4 ready-made review sets for this topic, by subtopic and marked SL or HL, 59 questions in all, to play as a class game on the projector. Free to host, and students join with a code.
A question from the sets
Trend in atomic radius across period 3?
- Increases
- Stays constant
- Increases then decreases
- DecreasesRight answer
What Structure 3 covers
Structure 3 classifies matter in two ways. S3.1 is the periodic table: blocks, groups and periods; the periodic trends in atomic and ionic radius, ionisation energy, electron affinity and electronegativity; the reactions of the group 1 metals and group 17 elements; the acid–base character of the oxides; and oxidation states. At higher level it adds the transition elements: variable oxidation states, ligands and complex ions, and why their compounds are coloured. S3.2 is organic: functional groups and homologous series, IUPAC names, structural isomers, and identifying compounds from mass spectra, infrared spectra and ¹H NMR spectra, with stereoisomers and ¹H NMR splitting patterns at higher level.
Where students slip
- Atomic radius falls across a period even though electrons are being added: the nuclear charge rises while the shielding stays almost the same, so the outer electrons are pulled closer.
- Propan-2-ol is a secondary alcohol. The class depends on how many other carbon atoms are bonded to the carbon carrying the –OH (two, here), not on where the –OH sits in the chain.
- HL Zinc is in the d-block but is not a transition element: neither the atom nor its only ion, Zn²⁺, has an incomplete d sublevel.
The sets
Play this set opens the set in splycr, where you can read every question and host it for your class straight away. Hosting needs no account, and students join with the code on the board. A free account lets you copy a set and edit it.
The questions were written for the splycr library by Biology by Bradford. Each one plays as multiple choice, and the three wrong options were written for that question.
Sets marked SL suit every IB Chemistry student, because higher level students study the standard level content too. Sets marked HL cover the additional higher level material: ten subtopics have an HL set after their SL one, and R1.4 Entropy and spontaneity, which is for higher level only, has an HL set of its own.
S3.1 The periodic table: Classification of elements
d-block element that is not a transition element?
Answer: Zinc
Transition metal complexes are coloured because ligands make the d orbitals…?
Answer: Split in energy
Unpaired electrons in a free Fe³⁺ ion (Z = 26)?
Answer: 5
S3.2 Functional groups: Classification of organic compounds
Class of compound with the linkage R–COO–R′?
Answer: Ester
Classification of propan-2-ol as an alcohol?
Answer: Secondary
Bond responsible for a strong IR absorption near 1700 cm⁻¹?
Answer: C=O
Non-superimposable mirror-image molecules?
Answer: Enantiomers
Which of these alcohols is chiral?
Answer: Butan-2-ol
¹H NMR splitting of a proton with three H atoms on the adjacent carbon?
Answer: Quartet
Game modes that suit this topic
Every set plays in all eight modes. These two fit this topic best.
Racer in teams
Periodic trends turn on direction: across a period or down a group, increases or decreases. In team Racer only one teammate sees the right option, so the team has to agree on the trend, and the reason for it, before anyone taps.
Kaboom
Organic names and functional groups (ester, carboxyl, propan-1-ol) are short answers, so the bomb moves fast and every student answers many times. Nobody is knocked out: the holder just loses points when it goes off.