Question

Elements are defined by the number of _______ they possess.
(A) electrons
(B) protons
(C) neutrons
(D) atoms

Answer 1

Hint: Elements are the simplest chemical substances in which all of the atoms are identical. We may characterise elements as a group of atoms with the same number of protons in their atomic nuclei. While an element's atoms all have the same amount of protons, they may have different neutron counts and hence different masses.

Complete answer:
An element is a pure material that cannot be broken down into simpler components by physical or chemical processes. An element is a pure material made up entirely of atoms with the same number of protons in their atomic nuclei, as defined by chemistry. Chemical elements, unlike chemical compounds, cannot be broken down chemically into simpler molecules. The atomic number (represented by the symbol Z) is the defining attribute of an element. Scientists are constantly interested in this number, and how it differs across various elements, because an atom of one element may be recognised from an atom of another by the number of protons in its nucleus. The atomic number is the number of protons in an atom (Z). This number is significant since it is unique for each element's atoms. An element's atoms all have the same number of protons, yet each element's atoms have a distinct number of protons. All helium atoms, for example, have two protons, but no other element has two protons.
Hence, option (A) is correct.

Note:
The International Union of Pure and Applied Chemistry had recognised a total of 118 elements by November 2016. The first 94 elements are found naturally on Earth, whereas the following 24 are created via nuclear processes. Almost all of the elements, with the exception of unstable radioactive elements (radionuclides) that decay fast, are commercially accessible in variable proportions. The discovery and synthesis of new elements is still a work in progress in science.