CHEM103 Study Guide - Quiz Guide: Atomic Number, Unified Atomic Mass Unit, Weighted Arithmetic Mean

• School: University of Alberta
• Department: Chemistry
• Course: CHEM103
• Professor: All

Document Summary

See student"s solutions manual for the above problems. Chapter 1: 1. 38, 1. 66, 1. 76 [6th ed: 1. 38, 1. 66, 1. 76 ] Chapter 2: 2. 20, 2. 49, 2. 72 [6th ed: 2. 20, 2. 49, 2. 72] Explain the terms "atomic number", "mass number", "atomic mass" and "isotopes" with respect to the element copper. The symbol for copper is cu. The atomic number is equal to the number of protons in an element. This number is easy to find as it is given above the element symbol in the periodic table. For cu it is equal to 29. The mass number is the sum of the number of protons and the number of neutrons. In other words, each isotope has its own mass number. An isotope is when an atom has the same number of electrons and protons but a different number of neutrons. Cu has two stable isotopes, one with 34 neutrons (~70%) and one with 36 neutrons (~30%).