Question

Based on the information in the table, which elements are most likely in the same periods of the periodic table?



Boron and carbon are likely together in one period because they have very close atomic masses, while gallium and germanium are likely together in another period because they have very close atomic masses.
Aluminum, boron, and carbon are likely together in one period because they were first isolated in the first half of the 1800s, while gallium and germanium are likely together in another period because they were first isolated in the second half.
Boron and carbon are likely together in one period because they each end in “-on,” while aluminum, gallium, and germanium are likely together in another period because they each end in “-ium.”
Aluminum, boron, and gallium are likely together in one group because they have the same number of valence electrons, and carbon and germanium are likely together in another group because they have the same number of valence electrons.

Answer 1

Boron and carbon are in the same period, and gallium and germanium are in the same period.

Reason: B and C have adjacent atomic numbers (period 2), and Ga and Ge have adjacent atomic numbers (period 4), so each pair lies in the same period. The first statement (pairing by close atomic mass/atomic number) is the correct choice.