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quester [9]
3 years ago
15

How many neutrons does element X have if its atomic number is 23 and its mass number is 90?

Physics
2 answers:
givi [52]3 years ago
4 0

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

Zina [86]3 years ago
4 0
<h2>Answer:</h2>

<u>The number of neutrons is </u><u>67</u>

<h2>Explanation:</h2>

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

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<h3>Further explanation</h3>

Matter is the building block of everything that we encounter in our lives. Matter is made of atoms, which are in turn made of tiny particles which are called electrons, protons, and neutrons. The ammount of these 3 elements, and their topological configuration in the atoms, is what determines what a certain element is (like Carbon, Hydrogen, Iron, etc).

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Joining both our expressions we can get that:

E= \frac{\lambda}{2\pi \epsilon_0 \cdot r}

<h3 /><h3>Learn more</h3>
  • Description on Electric fields: brainly.com/question/8971780
  • Relation between electric fields and magnetism: brainly.com/question/2838625
  • How can we use electric charges: brainly.com/question/10427437
<h3>Keywords</h3>

Electrons, protons, electric field, cylinder, electric flux

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