Lecture Presentation Chapter 4 Elements and Symbols Karen

Chapter 4 Atoms and Elements In addition to growing crops and raising animals, farmers must understand how to perform chemical tests and how to apply fertilizers and pesticides or herbicides to crops. General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C. Timberlake © 2016 Pearson Education, Inc.

Chapter 4 Readiness Key Math Skills • Using Positive and Negative Numbers in Calculations (1. 4 B) • Calculating Percentages (1. 4 C) • Rounding Off (2. 3) Core Chemistry Skills • Counting Significant Figures (2. 2) • Using Significant Figures in Calculations (2. 3) General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C. Timberlake © 2016 Pearson Education, Inc.

4. 1 Elements and Symbols Elements • are pure substances from which all other things are built. • cannot be broken down into simpler substances. • are listed on the inside front cover of this text. Learning Goal Given the name of an element, write its correct symbol; from the symbol, write the correct name. General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C. Timberlake © 2016 Pearson Education, Inc.

Some Elements and Their Names Element names come from planets, mythological figures, minerals, colors, geographic locations, and famous people. General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C. Timberlake © 2016 Pearson Education, Inc.

Chemical Symbols Chemical symbols • represent the names of the elements. • consist of one to two letters and start with a capital letter. One-Letter Symbols C carbon N nitrogen F fluorine O oxygen General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C. Timberlake Two-Letter Symbols Co cobalt Ca calcium Al aluminum Mg magnesium © 2016 Pearson Education, Inc.

Names and Symbols of Common Elements General, Organic, and Biological Chemistry: Structures of Life,

Chemical Symbols from Latin Names Ag silver (argentum) Au gold (aurum) General, Organic, and

Study Check Write the correct chemical symbols for each of the following elements: A. B. C. D. E. iodine iron magnesium zinc nitrogen General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C. Timberlake © 2016 Pearson Education, Inc.

Solution Write the correct chemical symbols for each of the following elements: A. B. C. D. E. iodine iron magnesium zinc nitrogen = = = I Fe Mg Zn N General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C. Timberlake © 2016 Pearson Education, Inc.

Study Check Give the names of the elements with the following symbols: A. B. C. D. E. P Al Mn H K General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C. Timberlake © 2016 Pearson Education, Inc.

Solution Give the names of the elements with the following symbols: A. B. C. D. E. P Al Mn H K = = = phosphorus aluminum manganese hydrogen potassium General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C. Timberlake © 2016 Pearson Education, Inc.

Chemistry Link to Health: Toxicity of Mercury (Hg) • is a silvery, shiny element that is a liquid at room temperature. • can enter the body by mercury vapor inhalation, contact with the skin, or ingestion of water or food contaminated with mercury. Once mercury has entered the body, it destroys proteins and disrupts cell function. Long-term exposure can • damage the brain and kidneys. • cause mental retardation. • decrease physical development. General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C. Timberlake © 2016 Pearson Education, Inc.

Chemistry Link to Health: Toxicity of Mercury contamination comes from • industrial wastes. • fish and seafood. • batteries. • compact fluorescent bulbs. General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C. Timberlake © 2016 Pearson Education, Inc.