What is the approximate atomic mass (in atomic mass units, u) of an atom that contains 26 protons, 26 electrons, and 19 neutrons?

• A. 26 u
• B. 71 u
• C. 52 u
• D. 45 u

Answer: (C)

Verified step by step guidance

1. Identify the number of protons, neutrons, and electrons in the atom. Here, protons = 26, neutrons = 19, and electrons = 26.
2. Recall that the atomic mass (in atomic mass units, u) is approximately the sum of the number of protons and neutrons, since electrons have negligible mass.
3. Write the formula for atomic mass: \(\text{Atomic Mass} \approx \text{Number of Protons} + \text{Number of Neutrons}\).
4. Substitute the given values into the formula: \$26 + 19$.
5. Add the numbers to find the approximate atomic mass in atomic mass units (u).