Question 1 · 1 mark · Difficulty 1/3
How is the periodic table arranged?
- By alphabetical order
- By increasing atomic number, with elements in groups having similar properties
- By mass only
- Randomly
Show answer & explanation
✓ Answer: B — By increasing atomic number, with elements in groups having similar properties
Elements are ordered by atomic number (protons). Vertical columns (groups) contain elements with similar chemical properties because they have the same number of outer electrons.