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118 elements · 12 drills · 3 modes

Periodic Table Quiz

Every symbol, name, number, and mass, learned one square at a time.

Board notes

What this quiz drills

All 118 elements, twelve different drills, three modes. You can work the whole table or narrow to one family, one period, or one block, and the quiz keeps a private record of which squares keep beating you so it can bring them back more often.

Everything below is the reference material the drills are built from. There is no account and no server: your progress lives in your own browser and nowhere else.

How to read the table

The layout is not decorative. Each row is a period, and it tells you how many electron shells an atom has. Each column is a group, and it tells you how many electrons are in the outermost shell. That second one is the whole trick, because outer electrons are what react. Elements in a column behave alike for that reason, which is why every noble gas is famously unreactive and every alkali metal below it goes off in water.

Blocks name the orbital being filled: the s-block on the far left, the sprawling p-block on the right, the d-block transition metals in the middle, and the f-block lanthanides and actinides. Those last two rows are printed underneath rather than in place for a purely practical reason. Slotting them where they belong would make the chart about three feet wide.

Periods hold 2, 8, 8, 18, 18, 32, and 32 elements. The jumps are new orbital types opening up.

The ten families

FamilyCountWhere and what
Alkali metals6Group 1 below hydrogen. Soft, and violently reactive with water.
Alkaline earth metals6Group 2. Reactive, but far better behaved than their neighbours.
Transition metals38The wide middle block. Iron, copper, gold, and most of what you would call a metal.
Post-transition metals11Softer, lower-melting metals after the middle block: aluminium, tin, lead.
Metalloids7The diagonal staircase. Half metal, half not, which is what makes silicon a semiconductor.
Nonmetals7The elements life is mostly built from: hydrogen, carbon, nitrogen, oxygen.
Halogens6Group 17. One electron short of full, so they grab. The salt formers.
Noble gases7Group 18. Outer shell already full, so they react with almost nothing.
Lanthanides15The first pulled-out row. The rare earths, which are not especially rare.
Actinides15The second pulled-out row. Every one of them radioactive.

The twelve drills

DrillWhat it asks
Smart mixRotates the six core drills and leans into the ones you miss most.
Name → findSee a name, click its square.
Symbol → findSee a symbol, click its square.
Number → findSee an atomic number and count your way to it. Drills the length of each period as much as the elements.
Where does it go?The board goes blank. Click where the element belongs.
Who's next door?One square is marked. Click its neighbour.
Name the elementA square lights up. Type its name.
Number → nameBlank board, an atomic number, type whose it is.
Give the symbolSee a name, type its symbol.
Atomic massSee an element, type its mass within one unit.
Heavier or lighter?Two elements, pick the heavier. Watch for the pairs where mass runs backwards.
Spell with symbolsBuild everyday words out of element symbols, like Ba·Co·N.

Atomic mass mostly climbs with atomic number, but not always. Argon outweighs potassium, cobalt outweighs nickel, tellurium outweighs iodine. Isotope abundance, not a printing error.

Three modes

Normal works through your chosen set once, retiring each element as you answer it. Learning uses spaced repetition instead: weak elements keep coming back and the round only ends when every one is mastered, which takes five quick correct answers in a row with no hint. Lightning gives you sixty seconds and unlimited questions, with streaks multiplying the score.

Points start at ten per question and decay the longer you take. A hint costs three, a wrong click costs two, and nothing ever drops below one.