Answer:
C) Isotope
Step-by-step explanation:
A) A cation is an atom or molecule with a positive charge resulting from a loss of electrons. It has more protons than electrons, and the value of its positive charge indicates how many electrons it lost. For example, potassium becomes a K+ ion after losing one electron. In this situation, neither Chlorine-45 nor Chlorine-42 are cations as there is no positive charge. Additionally, chlorine is more likely to form an anion than a cation due to its nonmetal nature.
B) An anion is an atom or molecule with a negative charge resulting from the gain of electrons. It has more electrons than protons, and the value of its negative charge indicates how many electrons it gained. Chlorine can form an anion by gaining one electron and becoming Cl-. However, in this question, there is no charge to indicate that there are chlorine anions involved.
C) Isotopes are atoms of a chemical element that have the same number of protons but different number of neutrons. They share similar chemical properties, but differ in their physical properties because of their different masses. Since isotopes have the same atomic number, they are differentiated by their mass number. In this case, Chlorine-45 and Chlorine-42 are both isotopes of chlorine, but the first has a mass of 45 while the latter has a mass of 42. Thus, the correct answer is C.) Isotope.
D) An element in chemistry is any substance that cannot be broken down by chemical processes. It can only be transformed or broken down into another element through nuclear reactions. Chlorine-45 and Chlorine-42 are both isotopes of the element Chlorine (Cl). It has an atomic number of 17 on the periodic table and belongs to the group of halogens.