Isotopes The number of protons in a nucleus determines the identity of the element. For example, any atom having will a If we to add an extra proton to the nu- cleus, we prot entirely different element. For example, would have an C (6 protons) 1 proton N prot On the other; we add an extra NEUTRON to a nucleus we simply end up with the same element, hand, if the nucleus would be unchanged. just a little heavier since the charge on PES of a given element have the same ATOMIC NUMBER but a different ATOMIC MASS. of protons but a differentnumber of neutrono. In other words, isotopes have the same nu neutrons. The most An isotope is identified by its mass umber, the sum of the protons and n isotope of Carbon has a number of 12 and can be written as Carbon-12, two other mass common isotopes are Carbo and Carbon-14. Despite their different mass numbers, all three carbon isotopes react the same way chemically. PARTI. Answer the questions based on the above reading. 1. What is an isotope? 2. In hyphen notation, what does the number after the element name signify? 3. How can you tell isotopes of the same element apart? 4. Here are three isotopes of an element: 12C a. The element is: b. The number 6 refers to the c. The numbers 12, 13, and 14 refer to the d. How many protons and neutrons are in the first isotope? P: N: e. How many protons and neutrons are in the second isotope? P: N How many protons and neutrons are in the third isotope? P N: