An atom has 86 electrons, 125 neutrons, and 82 protons. Which element is this atom, and what is its charge?

• A. Radon (Rn), neutral atom
• B. Lead (Pb), with a charge of 4+
• C. Lead (Pb), with a charge of 4-
• D. Lead (Pb), with a charge of 4-

Answer: (C)

Verified step by step guidance

1. Identify the element by its atomic number, which is equal to the number of protons. Here, the atom has 82 protons, so the atomic number is 82.
2. Use the atomic number to find the element on the periodic table. The element with atomic number 82 is Lead (Pb).
3. Determine the charge of the atom by comparing the number of electrons to the number of protons. The atom has 86 electrons and 82 protons.
4. Calculate the net charge by subtracting the number of protons from the number of electrons: \(\text{Charge} = \text{Electrons} - \text{Protons} = 86 - 82\).
5. Interpret the result: if the charge is positive, the atom is a cation; if negative, it is an anion. Use this to state the charge of the atom.