The number of _____ in an atom determines what type of element it is. A. molecules. B. neutrons. C protons. D. electrons

The number of protons in an atom determines what type of element it is. Therefore, the answer is (c).

An atom is the smallest unit of matter. An element is made of three smaller subatomic particles. The subatomic particles are protons, neutrons, and electrons. The protons and neutrons make up the center of an atom, which is known as the nucleus. The electrons travel around the nucleus within either electron orbitals or electron clouds. The electrons travel at extremely fast speeds. Thus, it is impossible to determine the location of an electron at any given time.

The modern periodic table is arranged by atomic number. The atomic number of an element is the number of protons within that element’s nucleus. Each element has a unique atomic number. Changing the number of protons within an element also changes the atomic number. Thus, changing the number of protons also changes the element that is being referenced.

Changing the number of electrons and neutrons within an atom does not change the type of element. Changing the number of electrons within an atom creates an ion. Changing the number of neutrons within an atom creates an isotope.

Each subatomic particle has a different charge. Protons are positively charged. Neutrons are neutrally charged. Electrons are negatively charged. Therefore, a neutrally charged atom that has no charge will have equal numbers of electrons and protons. When an atom gains or loses electrons, it becomes an ion. When an atom gains a negatively-charged electron, it becomes negatively charged. A negatively charged atom is called an anion. When an atom loses an electron, it becomes positively charged. A positively charged atom is called a cation.

When an atom gains or loess neutrons, an isotope is formed. The atomic mass of an element is the number of protons plus the number of neutrons within the nucleus of an element. Thus, isotopes of the same element have different atomic masses. Sometimes, the nuclei of isotopes become too large. Thus, they seek to stabilize via radioactive decay.

In summary, the number of protons within an atom determines which element it is. Atoms of the same element may have different numbers of electrons and neutrons. Ions are atoms of the same element that have different number of electrons. Isotopes are atoms of the same element that have different number of neutrons.