How many protons are present in a potassium ion (K^+)?

• A. 1
• B. 19
• C. 20
• D. 18

Answer: (B)

Verified step by step guidance

1. Recall that the number of protons in an atom is equal to its atomic number, which is a unique identifier for each element on the periodic table.
2. Identify the element potassium (K) on the periodic table and note its atomic number, which represents the number of protons in a neutral potassium atom.
3. Understand that the potassium ion (K^+) has lost one electron compared to the neutral atom, but the number of protons remains unchanged because protons define the element.
4. Therefore, the number of protons in the potassium ion (K^+) is the same as in the neutral potassium atom, which is the atomic number of potassium.
5. Conclude that the potassium ion (K^+) contains 19 protons, since potassium's atomic number is 19.