Answer:
- <em>Number of protons, Z = 14</em>
- <em>Number of neutrons, N = 14</em>
Explanation:
<u>1) About isotopes:</u>
<em>Isotopes</em> are different kind of atoms of the same element. Hence, they have the atomic number (Z), which is the number of <em>protons</em>, the same number of electrons (talking about to neutral atoms, not ions), and different <em>number of neutrons N).</em>
This is, it is the number of neutrons what distinguish different isotopes of an element.
<u>2) About the notation used to distinguish different isotopes:</u>
A superscript and a subscript, both to the left of the chemical symbol of the element, are used to <em>distinguish different isotopes</em>:
A ←------------- This superscript tells the mass number of the isotope
X ←--------- This is the chemical symbol of the element
Z ←-------------- This subscript is the atomic number of isotope
In our case, the notiation for the isotope of silicon is: ²⁸₁₄ Si
So, we have:
- 28 is the mass number (A)
- 14 is the atomic number (Z)
- Si is the chemical symbol.
Now, you can answer the questions of the <em>part A</em>:
- Number of protons: Z = 14
mass number = number of protons + number of neutrons
A = Z + N
⇒ N = A - Z = 28 - 14 = 14
In <u>conclusion</u>:
- Number of protons, Z = 14
- Number of neutrons, N = 14
