Practice problem
Image source: By Armtuk CC BY 2.0, via [Wikimedia Commons]
Based on the labeling of the periodic table shown above, the Halogens are a woah‾\underline{\phantom{woah}}woah.
Period, because they're a column.
Period, because they're a row.
Group, because they're a column.
Group, because they're a row.
Type a concept, like “slope” or “photosynthesis”.
