Question

based on the information in the table, which elements are most likely in the same periods of the periodic table?
facts about five elements
element atomic mass (amu) total electrons valence electrons year isolated
aluminum (al) 27 13 3 1825
boron (b) 11 5 3 1808
carbon (c) 12 6 4 1803
gallium (ga) 70 31 3 1875
germanium (ge) 73 32 4 1886
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

Explanation:

Step1: Recall periodic - table concept

Elements in the same period have the same number of electron - shells. The period number is related to the principal quantum number of the outermost shell. Also, atomic mass and the year of isolation are not determining factors for elements being in the same period. The ending of the element name is also not a valid criterion for period placement.

Step2: Analyze valence electrons and period

Elements in the same group have the same number of valence electrons. Aluminum (Al) and gallium (Ga) have the same number of valence electrons (3), so they are in the same group. But we are looking for elements in the same period.

Step3: Consider electron - shell relationship

There is no correct option among the given ones based on the information provided in a strict sense. However, if we consider that elements with a relatively small difference in the number of total electrons are more likely to be in the same period. Aluminum (13 electrons) and boron (5 electrons) are not in the same period. But if we assume we are looking at trends, elements with closer atomic numbers (related to electron numbers) tend to be in adjacent periods. But this is not a fool - proof method.

Since the question is about choosing from the given options:

Answer:

None of the options are correct as the criteria used in each option (atomic mass, year of isolation, element name ending) are not valid for determining elements in the same period. If we had to choose the least wrong option based on the fact that elements in the same group have the same valence electrons (even though the question asks for period), the last option about aluminum, boron, and gallium having the same number of valence electrons is related to group - not period, but among these options it shows some understanding of electron - related properties. But again, this is not answering the period question correctly. So, strictly speaking, there is no correct answer here.