Which element is represented by an atom that has 2 protons, 2 neutrons, and 2 electrons?

• A. Beryllium
• B. Hydrogen
• C. Lithium
• D. Helium

Answer: (D)

Verified step by step guidance

1. Identify the number of protons in the atom, as the number of protons determines the element's identity. Here, the atom has 2 protons.
2. Recall that the atomic number of an element is equal to the number of protons in its nucleus. The atomic number uniquely identifies the element on the periodic table.
3. Look up the element with atomic number 2 on the periodic table. This element is Helium (He).
4. Note that the number of neutrons (2) and electrons (2) do not change the element's identity but can affect the isotope and charge state.
5. Conclude that an atom with 2 protons, 2 neutrons, and 2 electrons corresponds to the element Helium.