"People who do not work in science are under the misapprehension that the scientist, because of his greater knowledge, must be irreligious; to the contrary our work brings us nearer to God." Ernest Rutherford (Nobel prize in Chemistry 1908)
INTRODUCTION: The building block of all matter is the atom. The word atomos means “indivisible” and was first used by Democritus in the 4th century B.C. This concept of the atom later returned in the atomic theory of John Dalton over 2200 years later. In the past 200 years atomic theory has dramatically changed, making the discovery of the structure of the atom one of science’s most exciting stories. Today we have a predominantly mathematical model of the atom called the Quantum Mechanical Model. Atomic structure is foundational to the study of Chemistry. In particular, the organization and behavior of electrons in the “electron cloud” provide the basis for the phenomena in Chemistry. In this unit we will learn about the historical experiments and process which shaped the story of the atom. We will discuss the current theory of the atom, learn about the importance of electron configurations, and about the unique behavior of unstable, radioactive nuclei.
OBJECTIVES:
As you study this unit, you should be able to do the following:
Summarize the development of the Modern Atomic Theory incorporating the contributions of Dalton, Thomson, Rutherford, Bohr and Schrodinger. (4.1, 4.2, 5.1)
Distinguish among protons, electrons, and neutrons in terms of their relative masses, charges and location in the atom. (4.3)
Infer the number of protons, electrons, and neutrons using the atomic number and mass number of an element. (4.3)
Explain how an element can become an ion in terms of sub atomic particles. Also infer the number of protons, electrons, and neutrons using the atomic number, mass number and charge of an ion. (4.3)
Differentiate between mass number and atomic mass, and calculate atomic mass given isotope mass and abundance data. (4.3)
Describe changes that occur in the nucleus of an atom when it undergoes radioactive decay. Write a nuclear equation for a and b particle decay. (25.1, 25.2)
Explain the significance of quantized energies of the Quantum Mechanical Model. (5.1, 5.3)
Describe atomic orbitals in terms of shape, size and relative energy. (5.2)
Apply the Aufbau principal, Pauli exclusion principal and Hund’s Rule to write electron configurations and orbital diagrams for elements. (5.2)
LEARNING ACTIVITIES:
These activities are to be completed and handed in parts.
To learn about objectives 1-5:
READ Chapter 4; pp. 101 – 118. See objectives for specific section.
WRITE ChemActivity 1: “The Nuclear Atom”
READ and PERFORM Lab Exploration “Ions and Atoms.” Record your data and observations in your "Student Lab Notebook."
WRITE answers to questions for “Ions and Atoms” in your "Student Lab Notebook." Label procedure and questions clearly.
WRITE answers to end of the chapter questions 36, 38, 40 – 48, 50, 53, 55, 61, 65, 74, 81; pp. 122-123.
PRACTICE with the “Standardized Test Prep” page at the end of chapters 4 p. 125. Then CHECK your answers on the web site.
Quiz on objectives 1-5: – Monday Oct. 1. Ch. 4 Homework due Monday, Oct. 1
To learn about objective 6:
READ Chapter 25.1 and 25.2, pp. 799 – 808.
WRITE "3-4 Explore" Worksheet on Nuclear equations
WRITE answers to end of chapter questions 47, 49, 58, 59 on p. 822.
To learn about objectives 1, 7-9:
READ all of Chapter 5, pp. 127-145.
WRITE answers to end of the chapter questions 22, 23, 24, 26-28, 30-34, 39, 50, 52, 60, 64, 68, 71; pp. 149 – 151.
To make sure you understand the objectives for this unit:
ASK me, the teacher, any lingering QUESTIONS
TAKE the Unit’s Self-Test and consult the “Standardized Test Prep” pages at the end of chapters 4 and 5, pp. 125 and 153. Then CHECK your answers on the web site or on the board in class.
Unit Test Monday, October 15. Ch. 25 and Ch. 5 homework due same day as Test.
