Question

Calculate the number of electrons, protons, and neutrons in $^{89}{{Y}_{39}}$.

Answer 1

Hint: Electrons, protons, and neutrons are the three main particles in the atom and this can be easily found by the atomic number and mass number of the element. The atomic number can be used to find the number of electrons and protons and the mass number can be used to find the number of neutrons in the element.

Complete answer:
We know that an atom is not the smallest particle in nature, so there are many particles inside the atom. So, the three most important particles inside the atoms are electrons, neutrons, and protons. These have charge, i.e., an electron has a unit negative charge, a proton has a unit positive charge, and a neutron doesn't have any charge.
The atomic number can be used to find the number of electrons and protons and the mass number can be used to find the number of neutrons in the element.
So, the given element is $^{89}{{Y}_{39}}$, in which the atomic number is equal to 39 and the mass number is equal to 89.
The atomic number indicates the number of electrons in the atom. Since the atomic number is 39, the number of electrons is 39. As the number of protons is equal to the number of electrons, so the number of protons is also 39.
The mass number is equal to the sum of the number of electrons and the number of neutrons in the atom. The mass number of the element is 89. So, the number of neutrons is:
$89=39+\text{ number of neutrons}$
$\text{Number of neutrons = 89 - 39 = 50}$
Therefore, the number of neutrons is 50 in $^{89}{{Y}_{39}}$.

Note:
The number of electrons and protons are the same in the neutral atom, but if the number of electrons is not the same as the number of protons then it ions, these can be cation or anion.