Question

1. a chemistry student examines data for three different atoms of oxygen.

• atom j: 8 protons, 8 neutrons, 8 electrons
• atom k: 8 protons, 9 neutrons, 8 electrons
• atom l: 8 protons, 10 neutrons, 8 electrons

what can the student conclude about the relationship between these atoms?
they are different elements because they have different numbers of neutrons.
they are the same element but different isotopes because they have different numbers of neutrons.
they are ions of the same element because they have different numbers of neutrons.
they are the same element with identical properties because they have equal protons and electrons.

Explanation:

Elements are defined by the number of protons. Since all three atoms have 8 protons, they are the same element (oxygen). Isotopes of an element have the same number of protons but different numbers of neutrons. Here, the three oxygen - atoms have different numbers of neutrons. Ions are atoms with a net electric charge due to a loss or gain of electrons, but these atoms have equal numbers of protons and electrons, so they are neutral. Also, isotopes have slightly different physical properties due to different masses.

Answer:

They are the same element but different isotopes because they have different numbers of neutrons.