Question

How many neutrons does Uranium-238 have if it has 92 protons?

Answer 1

Hint As we know that protons are positively charged, electrons are negatively charged. If we have to find the number of neutrons, we will subtract the atomic number from the mass number. And we can easily find the electrons, neutrons and protons.

Complete answer:
- As we all know that atomic number denotes the total number of protons present in the nucleus of an atom. As we are provided with the information that the mass number of uranium is 238, and we know that the atomic number of uranium is 92.
- It is found that the number of protons is equal to the atomic number. This clearly means that any atom which is an isotope of uranium will basically have 92 protons in the nucleus.
- And the number of electrons is equal to the proton number. Hence, we can say that there will be 92 electrons.
- Now, we will calculate the number of neutrons present. As we know that mass number= number of protons + number of neutrons. Hence, the number of neutrons will be = 238-92=146.

- Hence, we can conclude that there are 92 protons, 146 neutrons and 92 electrons are present in an atom of Uranium-238.

Note:
- We should note that the total number of neutrons present in the nucleus is equal to the difference between the atomic number and the mass number of an atom.
- As we know that the mass number of any atom is basically equal to the addition of the protons and neutrons that are present in the nucleus.