Question

which statement is completely accurate?
○ atoms of the same element always have different atomic weights.
○ atoms of the same element can have different numbers of neutrons.
○ atoms of the same element always have different numbers of neutrons.
○ atoms of the same element can have neutrons but exist without protons.

Explanation:

• Atoms of the same element have a fixed number of protons (defining the element). Isotopes are atoms of the same element with different neutron counts, which can lead to different atomic weights, but not all atoms of an element always have different weights (many elements have a dominant isotope).
• The first statement is false because many elements have a primary isotope, so same-element atoms can have the same atomic weight.
• The third statement is false because not all atoms of the same element must have different neutrons; most elements have a common isotope with a standard neutron count.
• The fourth statement is false because an atom cannot exist without protons (the number of protons defines the element; a particle without protons is not an atom of any element).
• The second statement is true because isotopes (same element, different neutron numbers) are a well-established atomic property.

Answer:

Atoms of the same element can have different numbers of neutrons.