The number of protons in an atom is called the atomic number. The number of protons plus the number of neutrons is the mass number. When an acid is added to a base, a chemical reaction occurs. The reaction produces water and a salt. Also, each elemnet is represented by a symbol- a capital letter followed by one or two lowercase letters.
Atoms are the building blocks of matter.
All atoms have a core called a nucleus containing protons and neutrons. Protons have a positive electric charge. Neutrons have no electric charge. The number of protrons equals the number of electrons. A property is a quality or characteristic of matter.