Question

Carbon has an atomic number of 6. How many protons and neutrons are in the nucleus of carbon- 13?

Answer 1

Hint We know that carbon- 13 is an isotope of carbon. Firstly we should understand the atomic structure representation in periodic tables, about the nucleus of an atom and the concept of isotope. etc., in order to answer this question within no time.

Complete step by step solution:
Nucleus consists of protons (P) and neutrons (N).
Now, let’s see the representation atom structure in the periodic table.
Where, X is the element
A is the mass number
Z is the atomic number
Mass number can be defined as the mass of the atom. The number of protons present in the nucleus is known as atomic number.
The relationship between A and Z is,
A= Z+ N………………………….equation 1
Where, N is the number of neutrons.
Atomic number = Number of protons = Number of electrons
Z= P= e…………………………equation 2
Where, P is the number of protons
 e is the number of electrons.
 Isotopes of an element can be defined as the different atomic mass exhibited by the element but have the same atomic number.
As carbon has three isotopes they are: $C^{12}$, $C^{13}$, $C^{14}$. These isotopes have the same atomic number which is 6.
With reference to equation 2 we can conclude that the proton present in C-13 is 6.
We know, atomic mass (A) is 13.
Number of proton (P) = 6
Substituting these value in equation we can find number of neutrons present in C-13:
A = Z+ N ( Z = P)
13 = 6 + N
N = 7
Thus in C-13, the number of neutrons present is 7 and the number protons present is 6.

Note: C-13 is an isotope of the carbon. In the case of isotopes only the atomic mass differs not the atomic number. In other words we can say that the number of protons remains the same in the isotopes of an element, there will be a difference in the number of neutrons. So, C-12 has 6 neutrons, C-13 has 7 neutrons and c-14 has 8 neutrons in its nucleus.