Question

Complete the sentences:

I) The atomic number of an atom is the number of:

1.Neutrons
2.Protons
3.Electrons
4.Isotopes

II) The mass number of an atom is the number of:

1.Protons
2.Electrons
3.Neutrons
4.Isotopes

Answer 1

I) The atomic number of an atom corresponds to the number of protons (2), while the mass number is the sum of protons and neutrons in the nucleus.

II) Isotopes have the same atomic number but different numbers of neutrons (3). Subtracting the atomic number from the mass number yields the number of neutrons.

Step-by-step explanation:

To complete the sentences regarding atomic structure:

1. The atomic number of an atom is the number of protons present in the nucleus.
2. The mass number of an atom is the sum of protons and neutrons.

An element's atomic number is critical for determining its identity as it is equal to the number of protons within an atom. The number of protons also influences the number of electrons in a neutral atom because they are equal. Isotopes of an element have the same number of protons but different numbers of neutrons. The mass number, often confused with atomic mass, represents the sum of protons and neutrons in the atom's nucleus and doesn't include the mass contributed by electrons.

Therefore, to find the number of neutrons, one simply subtracts the atomic number from the mass number. This is crucial for understanding the structure and properties of different elements and their isotopes.