To determine which element contains 25 protons, we refer to the atomic number of elements. The atomic number, also known as the proton number, is a unique identifier for each chemical element and indicates the number of protons in an atom of that element.
Here are the atomic numbers for the given elements:
1. Magnesium (Mg): The atomic number of magnesium is 12, which means magnesium atoms have 12 protons.
2. Aluminum (Al): The atomic number of aluminum is 13, indicating that aluminum atoms contain 13 protons.
3. Tin (Sn): The atomic number of tin is 50, meaning tin atoms have 50 protons.
4. Manganese (Mn): The atomic number of manganese is 25, which means manganese atoms contain 25 protons.
Therefore, the element that contains 25 protons is manganese [tex]$(Mn)$[/tex].
