Periodic table The periodic table lists two main numbers for each element. The atomic number is an integer that equals the number of protons. The number of neutrons is not given in the periodic table because it will vary with different isotopes. The mass number of an element is the sum of the protons and neutrons. To find the number of neutrons, the atomic number must be subtracted from the mass number. Elemental symbol When writing the symbol for an element, a superscript indicates the mass number and a subscript indicates the atomic number. For example, C has a mass number of 14 and an atomic number of 6. This isotope can also be written as just ¹4C. You do not need to put in the 6 because the atomic number of carbon is always 6 regardless of which isotope you are dealing with. Part B . VE ΑΣΦ Part A A certain element X has four isotopes. How many neutrons are found in one atom of 59 Co? Express your answer numerically. View Available Hint(s) ➜ number Elemental symbol When writing the symbol for an element, a superscript indicates the mass number and a subscript indicates the atomic number. For example, C has a mass number of 14 and an atomic number of 6. This isotope can also be written as just C. You do not need to put in the 6 because the atomic number of carbon is always 6 regardless of which isotope you are dealing with. 4.350% of X has a mass of 49.94605 amu. . 83.79% of X has a mass of 51.94051 amu. . 9.500% of X has a mass of 52.94065 amu. . 2.360% of X has a mass of 53.93888 amu. What is the average atomic mass of element X? Express your answer numerically to four significant figures. ► View Available Hint(s) ΕΙ ΑΣΦ Submit Atomic mass Since the number of neutrons varies in the periodic table, neither the number of neutrons nor the mass number (number of neutrons plus protons) is shown. What we do see is the atomic mass, or a weighted average of all the isotope masses. This is the noninteger listed with an element, it is the number with several decimal places. An elements atomic mass is the weighted average of the isotope masses. In other words, it is an average that takes into account the percentage of each isotope. To find the weighted average, multiply each isotopic mass by its relative abundance and find the sum for each isotope of an element Bod Part C amu What is the identity of element X from Part B? Express your answer as a chemical symbol. Submit Request Answer Part D ? o a O C The two isotopes of chlorine areCl and C1. Which isotope is the most abundant? 4 View Available Hint(s)