Answer:
They have all the same number of protons and electrons ( 6)
Explanation:
Carbon 12, Carbon 13 and Carbon 14 are all isotopes of Carbon.
The definition of an isotope is: They have the same number of protons (and electrons), but a different number of neutrons. Different isotopes of the same element have different masses.
Carbon 12 means an isotope with mass 12 u
it has 6 protons,(and 6 electrons) and 6 neutrons : 6 neutrons + 6 protons = 12
Carbon 13 is an isotope with mass 13 u
It has the same amount of protons ( and electrons) as Carbon 12, so 6 protons and 6 electrons
13 - 6 = 7 ⇒ Carbon 13 has 7 neutrons
Carbon 14 is an isotope with mass 14
it has the same of protons ( and electrons) as Carbon 12 and Carbon 13, so 6 protons and 6 electrons
14 - 6 = 8 ⇒ Carbon 14 has 8 neutrons
We can conclude that Carbon 12, Carbon 13 and Carbon 14 are 3 isotopes of Carbon. They all have the same number of protons (and electrons) = 6.
This means the isotopes will also have the same atomic number, because they are all isotopes of the same element.