Respuesta :
Answer:
67
Explanation:
- The atomic number (Z) of an atom is equal to the number of protons in the nucleus
- The mass number (A) of an atom is equal to the sum of protons and neutrons in the nucleus
Therefore, calling p the number of protons and n the number of neutrons, for element X we have:
Z = p = 23
A = p + n = 90
Substituting p=23 into the second equation, we find the number of neutrons:
n = 90 - p = 90 - 23 = 67
Answer:
The number of neutrons is 67
Explanation:
As we know that the atomic number is the number of protons. If we subtract the atomic number from the mass number, we can actually find the number of neutrons.
So
Number of neutrons = Mass number - atomic number
Neutrons = 90 - 23 = 67