What is matter composed of atoms with the same number of positive and negative charges called?

Matter composed of atoms with the same number of positive and negative charges is referred to as elements. Elements are substances that cannot be broken down into simpler substances by chemical means and are defined by their atomic structure. Each element consists of atoms that have an equal number of protons, which carry a positive charge, and electrons, which carry a negative charge. This balance of positive and negative charges results in a neutral electrical state for the atom, which is fundamental to the identity of the element.

In contrast, compounds are substances formed when two or more different types of atoms bond together. Molecules consist of two or more atoms that may be of the same or different elements, and mixtures are combinations of two or more substances that retain their individual properties. None of these definitions apply to the description of matter comprising atoms with equal numbers of positive and negative charges, making elements the correct answer.