Which of the following is the number of protons in a krypton (Kr) atom?

• A. 18
• B. 84
• C. 48
• D. 36

Answer: (D)

Verified step by step guidance

1. Recall that the number of protons in an atom is given by its atomic number, which is unique for each element.
2. Identify the element in question, which is krypton (Kr).
3. Look up the atomic number of krypton on the periodic table; this number represents the number of protons in a krypton atom.
4. Note that the atomic number of krypton is 36, meaning it has 36 protons.
5. Understand that the other numbers given (18, 84, 48) correspond to different properties or elements, but only the atomic number (36) correctly represents the number of protons in krypton.