How many protons are contained in the 86Kr atom?

How many protons are contained in the 86Kr atom?

• A. 36
• B. 50
• C. 86
• D. 49

Answer: (A)

The number of protons in an atom is defined by its atomic number. For krypton (Kr), the atomic number is 36. This means that every atom of krypton contains 36 protons in its nucleus. The mass number, which is sometimes confused with the number of protons, refers to the total number of protons and neutrons in the nucleus but is not relevant when identifying the number of protons specifically. Therefore, the correct choice reflects that there are 36 protons in the 86Kr atom.

The number of protons in an atom is defined by its atomic number. For krypton (Kr), the atomic number is 36. This means that every atom of krypton contains 36 protons in its nucleus. The mass number, which is sometimes confused with the number of protons, refers to the total number of protons and neutrons in the nucleus but is not relevant when identifying the number of protons specifically. Therefore, the correct choice reflects that there are 36 protons in the 86Kr atom.