How many protons are in manganese-55?
${}_{25}^{55} Mn$
A. 30
B. 55
C. 25
Answer (1)
The number of protons is equal to the atomic number.
Identify the atomic number of Manganese-55 from the notation 25 55 M n , which is 25.
Therefore, the number of protons in Manganese-55 is 25 .
Explanation
Understanding the Notation We are asked to find the number of protons in Manganese-55, which is represented as 25 55 M n . In this notation, the subscript (25) represents the atomic number, and the superscript (55) represents the mass number.
Atomic Number and Protons The atomic number of an element is defined as the number of protons in the nucleus of an atom of that element. Therefore, the number of protons in Manganese-55 is equal to its atomic number.
Determining the Number of Protons Since the atomic number of Manganese-55 is 25, it has 25 protons.
Final Answer Therefore, the number of protons in manganese-55 is 25 .
Examples
Understanding the number of protons in an atom is crucial in many fields. For example, in nuclear medicine, radioactive isotopes like Manganese-52 (which has 25 protons and a different number of neutrons) are used in PET scans to image organs and tissues. Knowing the number of protons helps scientists predict how these isotopes will behave and interact with the body. Similarly, in materials science, the number of protons (and thus the element's identity) determines the chemical properties of a material, which is essential for designing new materials with specific functions.
