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Please answer each part of the question for full points. Thanks in advance. Usin

ID: 2103371 • Letter: P

Question

Please answer each part of the question for full points. Thanks in advance.

Using the periodic table found in your book (or the link posted on our class web site for the Periodic Table of Isotopes), you can see that as the elements get more and more massive, the number of neutrons increases compared to the number of protons. Those additional protons are necessary to help glue the nucleus together. What are the neutron and proton numbers for the most common isotopes of Carbon (C), nitrogen (N), and oxygen (O)? What is the ratio of neutrons to protons for the stable isotopes of these three elements? [Ratio = (number of neutrons) / (number of protons)] Taking three elements near the middle of the periodic table, silver (Ag), cadmium (Cd), and indium (In), find the number of neutrons and protons for each in the same way. Compute the ratio of neutrons to protons for the elements in part (c) above and find the average ratio. Repeat the process of parts (c) and (d) above for thorium (Th), protactinium (Pa), and uranium (U). Compare the ratios of parts b, d, and e above. If a large element like uranium were to somehow break up into two medijm-sized elements, can you see that there will be extra neutrons left over? About how many extra neutrons will be left over for each atom of U that disintegrates?

Explanation / Answer

For any element


atomic no = A and mass no = Z


Protons = A and Neutrons = Z-A


For carbon


A= 6 and Z = 12


protons = 6 and neutrons = 6


For Nitrogen


A= 7 and Z=14


protons = 7 and neutrons =7


For Oxygen


A=8 and Z = 16


Protons = 8 and neutrons = 8


Ratio of neutrons to protons is 1 in all cases


For Silver


A= 47 and Z =108


protons = 47 and Neutrons = 61


Ratio = 1.298


For cadmium


A = 48 and Z = 112


protons = 48 and neutrons = 64


Ratio = 1.333


For Indium


A = 49 and Z =115


Protons = 49 and neutrons =66


Ratio = 1.347


For Thorium


A= 90 and Z = 232


Protons = 90 and Neutrons = 142


Ratio = 1.578


For Protactinium


A = 91 and Z = 231


protons = 91 and neutrons = 140


Ratio = 1.539


For Uranium


A =92 and Z =238


Protons = 92 and Neutrons = 146


Ratio = 1.587