Question 2.3: Name the elements given in Example 2.2 and write the symbols...
Name the elements given in Example 2.2 and write the symbols for their atomic nuclei
Strategy
Determine the atomic number (the number of protons in the nucleus) and then locate the element in the Periodic Table on the inside front cover.
Solution
(a) This element has 58 protons. We find in the Periodic Table that the element with atomic number 58 is cerium, and its symbol is Ce. An atom of this element has 58 protons and 78 neutrons, and therefore, its mass number is 136. We call it cerium-136. Its symbol is ^{136}_{58}Ce.
(b) This atom has 17 protons, making it a chlorine (Cl) atom. Because its mass number is 37, we call it chlorine-37. Its symbol is ^{37}_{17}Cl
Problem 2.3
Name the elements given in Problem 2.2. Write the symbols of their atomic nuclei.