What is the approximate atomic mass (in atomic mass units, u) of an atom that contains 26 protons and 30 neutrons?

• A. 30 u
• B. 56 u
• C. 86 u
• D. 26 u

Answer: (B)

Verified step by step guidance

1. Identify the number of protons and neutrons in the atom. Here, the atom has 26 protons and 30 neutrons.
2. Recall that the atomic mass (in atomic mass units, u) is approximately the sum of the number of protons and neutrons because 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: \(\text{Atomic Mass} \approx 26 + 30\).
5. Add the numbers to find the approximate atomic mass in atomic mass units.