Carbon-14 is an isotope of carbon. how does it differ from other forms of carbon?

Carbon-14, also known as radiocarbon, is a radioactive isotope of carbon as compared to other forms of carbon. it contains 6 protons and 8 neutrons. The presence of such in organic materials is the basis of the radiocarbon dating method to date geological samples.

the catch is that the top numbers are atomic masses the bottom numbers are the numbers of protons and electrons in an uncharged atom. they are the number of that atoms as you would find them on the periodic table. further, the numbers on the left are used to determine the missing numbers on the right

so here we go

atomic mass

239 + 1 = y + 134 + 3 combine like terms

240 = y + 137             subtract 137 from both terms

240 - 137 = y

103 = y

atomic number

94 = z +54 + 0

94 = z + 54               subtract 54 from both sides.

40 = z

answer

The mass has escaped into a gas which you can not see so the law stays true.