Find the element
Click the element on the periodic table.
The periodic table groups elements by their electron structure: 7 rows (periods) and 18 columns (groups), plus the lanthanide and actinide rows below. This quiz shows the full table and asks you to click the named element. Right clicks turn green, missed cells turn red, and the grid fills up over the run so you see your progress at a glance.
How many questions?
Frequently asked questions
How is the periodic table organised?
Elements are arranged in order of atomic number across seven rows (periods) and eighteen columns (groups). Elements in the same group share similar chemistry because they have the same number of electrons in their outermost shell.
Why are lanthanides and actinides shown as separate rows?
They belong to periods 6 and 7 but inserting all 14 elements of each into the main grid would make the table impractically wide. Pulling them out keeps the table at 18 columns while preserving the underlying order.
What's the difference between a group and a period?
A group is a vertical column (1 to 18). A period is a horizontal row (1 to 7). The group tells you about valence electrons and reactivity; the period tells you about the highest occupied electron shell.
What do the rows of the periodic table tell you?
Each row corresponds to a new outer electron shell. Period 1 has two elements (filling the 1s shell); period 2 fills the 2s and 2p subshells, and so on. The heavier rows include d- and f-orbital filling.