GENERAL GEOLOGY

Detailed explanation-1: -Isotopes. An isotope is one of two or more forms of the same chemical element. Different isotopes of an element have the same number of protons in the nucleus, giving them the same atomic number, but a different number of neutrons giving each elemental isotope a different atomic weight.

Detailed explanation-2: -Isotopes are atoms with different atomic masses which have the same atomic number. The atoms of different isotopes are atoms of the same chemical element; they differ in the number of neutrons in the nucleus.

Detailed explanation-3: -Metals, metalloids, and nonmetals are the three types of elements, whereas main-group elements, transition metals, and inner transition metals are the three types of transition metals.

Detailed explanation-4: -Atoms of the same element always have the same number of protons, same Z, but often have different numbers of neutrons, therefore, different mass numbers.

Detailed explanation-5: -All atoms of the same element have the same number of protons, but some may have different numbers of neutrons.