How many neutrons are contained in the isotope ruthenium-101 (Ru-101)?

• A. 44
• B. 101
• C. 57
• D. 101 - 44 = 57

Answer: (C)

Verified step by step guidance

1. Identify the atomic number (Z) of ruthenium (Ru), which is the number of protons in the nucleus. For ruthenium, Z = 44.
2. Note the mass number (A) of the isotope, which is given as 101 in Ru-101. The mass number represents the total number of protons and neutrons in the nucleus.
3. Recall the relationship between mass number, protons, and neutrons: \(A = Z + N\), where \(N\) is the number of neutrons.
4. Rearrange the formula to solve for the number of neutrons: \(N = A - Z\).
5. Substitute the known values into the equation: \(N = 101 - 44\), which will give the number of neutrons in the isotope.