Final answer:
Among the presented statements, the true one is that phosphorus is more like silicon than it is like nitrogen. This is because they share many chemical properties and have similar electron configurations, as they are both in the same period.
Step-by-step explanation:
The student has presented multiple statements and is seeking to identify which one is true. To ascertain the correctness of each statement, we can rely on periodic trends and elemental properties. Let's examine each statement:
- Phosphorus has more valence electrons than nitrogen. This is true because phosphorus, being one element down in the same group as nitrogen in the periodic table, has the same number of valence electrons plus an additional energy level.
- Carbon has fewer protons in its nucleus than nitrogen. This statement is incorrect because carbon (atomic number 6) indeed has fewer protons than nitrogen (atomic number 7).
- Phosphorus is more like silicon than it is like nitrogen. This statement is generally considered true. Phosphorus and silicon are in the same period and share many chemical properties due to their similar electron configurations in the outer shell, whereas nitrogen has different properties and is in a different period.
- Aluminum is smaller than carbon. This statement is false. As per the periodic trend of atomic radii, carbon, being to the right and above aluminum in the periodic table, is smaller than aluminum.
Consequently, the true statement among the presented options is that phosphorus is more like silicon than it is like nitrogen (Statement C).