General organic and biological chemistry structures off life 5th CH4 elements and symbols GOB structures 5th ed

Lecture Presentation Chapter Elements and Symbols Karen C Timberlake General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Chapter 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 Readiness Key Math Skills • Using Positive and Negative Numbers in Calculations (1.4B) • Calculating Percentages (1.4C) • 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 Two-Letter Symbols C carbon Co cobalt N nitrogen Ca calcium F fluorine Al aluminum O oxygen Mg magnesium General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Names and Symbols of Common Elements General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Chemical Symbols from Latin Names Ag silver (argentum) Au gold (aurum) General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc 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 Lewis Symbols Lewis Symbols for Selected Elements in Periods to General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Study Check Write the electron-dot symbol for each of the following elements: Cl, C, N General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Solution Write the electron-dot symbol for each of the following elements: Cl, C, N Cl General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake C N © 2016 Pearson Education, Inc Atomic Size Atomic size • is determined by the atom’s atomic radius, the distance between the nucleus and the outermost electrons • increases for representative elements from top to bottom of the periodic table • decreases within a period as a result of increased number of protons in the nucleus General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Atomic Size For representative elements, the atomic size increases going down a group but decreases going from left to right across a period General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Ionization Energy Ionization energy is the energy required to remove one of the outermost electrons Na(g) + energy (ionization)  Na+(g) + e− • As the distance from the nucleus to the valence electrons increases, the ionization energy decreases • The ionization energy is low for metals and high for the nonmetals General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Ionization Energy Ionization energy decreases down a group and increases going across a period from left to right General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Metallic Character An element with metallic character is one that loses valence electrons easily Metallic character • is more prevalent in metals on the left side of the periodic table • is less for nonmetals on the right side of the periodic table that not lose electrons easily • decreases going down a group, as electrons are farther away from the nucleus General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Metallic Character The metallic character of the representative elements increases going down a group and decreases going from left to right across a period General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Summary of Trends in the Periodic Table General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Study Check Given the elements C, N, and Cl, A which is the largest atom? B which has the highest ionization energy? C which belongs to Group 5A (15)? General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Solution Given the elements C, N, and Cl, A which is the largest atom? C B which has the highest ionization energy? C which belongs to Group 5A (15)? N General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake Cl © 2016 Pearson Education, Inc Study Check Complete each of the following statements with decreases or increases A Going down Group 6A (16), the ionization energy _ B Going across Period 3, from left to right, the atomic size _ C Going down Group 2A (2), the metallic character _ General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Solution Complete each of the following statements with decreases or increases A Going down Group 6A (16), the ionization energy decreases B Going across Period 3, from left to right, the atomic size decreases C Going down Group 2A (2), the metallic character increases General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Concept Map General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc ... 1−7 General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Periodic Table of Elements General, Organic, and Biological Chemistry: Structures. .. insulators General, Organic, and Biological Chemistry: Structures of Life, 5/e Karen C Timberlake © 2016 Pearson Education, Inc Comparing a Metal, a Nonmetal, and a Metalloid General, Organic, and Biological. .. 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