Final answer:
Ce(4⁺), with a 4+ charge, indicates a loss of 4 electrons compared to the number of protons, resulting in the largest difference between protons and electrons among the options provided.
Step-by-step explanation:
The student's question is focused on identifying which species has the largest difference between the number of protons and the number of electrons. To determine this, we analyze the charge of each given ion since the charge directly indicates the difference in quantity between protons and electrons. Here are the ions with their respective differences:
- Ti(2⁺): Titanium normally has 22 protons. As Ti²⁺, it loses 2 electrons, which means it has 20 electrons. Difference = 22 - 20 = 2.
- P (3⁻): Phosphorus normally has 15 protons. As P³⁻, it gains 3 electrons, which means it has 18 electrons. Difference = 15 - 18 = 3.
- Mn: Manganese has 25 protons and 25 electrons in its neutral state. Difference = 0.
- Se (2⁻): Selenium normally has 34 protons. As Se²⁻, it gains 2 electrons, which means it has 36 electrons. Difference = 34 - 36 = 2.
- Ce (4⁺): Cerium normally has 58 protons. As Ce⁴⁺, it loses 4 electrons, which means it has 54 electrons. Difference = 58 - 54 = 4.
The species with the largest difference between the number of protons and electrons is Ce (4⁺) with a difference of 4.