Atomic numbers are determined by the number of protons an atom has. The mass number is determined by the number of protons and neutrons. While the number of protons can't change (as the element itself would change), neutrons can and do vary. These are called isotopes.
The number of protons in an atom determines its atomic number, which is the same for all calcium atoms (20). The mass number of an atom is the sum of its protons and neutrons. The different mass numbers for these calcium atoms are due to variations in the number of neutrons, resulting in isotopes of calcium.
The atomic number of calcium is 20.
The most common calcium isotope, calcium-40, has 20 neutrons.
The atomic number of calcium is 20.
The atomic number of Calcium is 20.
Calcium is a metal element. atomic number of it is 20.
The number of neutrons is the difference between the Atomic Mass of an isotope and the atomic number of the element; each isotope of calcium has a different number of neutrons. See the link below for calcium isotopes.
Because different elements have different numbers of protons, which determines the atomic number.
Calcium is a meta element. Atomic number of it is 20.
The atomic number of calcium is 20. The atomic number tells you the number of protons in the nucleus of a calcium atom, which also corresponds to the number of electrons in a neutral calcium atom.
Atoms that have the same atomic number but different neutron numbers are known as isotopes. Isotopes of an element have the same number of protons but different numbers of neutrons, leading to variations in their atomic mass.
The different mass numbers are due to different numbers of neutrons.