What are common mistakes students make with the periodic table?

Question

Sebastian Alvarado · Accepted Answer

The alkali metals in group 1, for instance, (lithium, sodium, potassium, rubidium, cesium, and francium) have a number of characteristics in common. For instance, when pure (a solid piece of lithium, for instance), they react violently with water, with the strength of this reaction increasing as one moves down the group.

Elements in the same group have the same number of electrons in their outermost orbital, which is a primary determinant of how an element will behave in a chemical reaction; in contrast, elements in the same period have less in common. This is because elements in the same period have the same number of orbitals, or "energy levels" for their electrons.

Another common mistake occurs when listing the electron configuration of elements. Simply put, many students forget that the 3#d# sub-orbital is filled after the 4#s# sub-orbital; it can be confusing to find sub-orbitals for one orbital being filled after the first sub-orbital for the next orbital has been filled.

Furthermore, errors can occur in relation to the lanthanide and actinide series. Many students will inadvertently overlook them entirely due to their placement on most periodic table versions outside of their expected position.

Sebastian Alvarado · Answer

undefined Common mistakes students make with the periodic table include:
1. Confusing atomic number with atomic mass.
2. Misunderstanding the organization of elements by periods and groups.
3. Failing to recognize the significance of the periodic trends such as electronegativity, ionization energy, and atomic radius.
4. Not understanding the difference between metals, nonmetals, and metalloids.
5. Incorrectly interpreting the information provided in the periodic table, such as the meaning of symbols, atomic numbers, and chemical symbols.