Pop Quiz. Bio 105: Chemistry. Chemistry. Outline. Elements in Nature. Chemistry Matter Anything that takes up space and has mass 1/21/2016

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1 Pop Quiz Bio 105: hemistry Lecture 2 Reading: hapter 2 (Pages 20-39) Name four common characteristics of living organisms. All the factors in an experiment that are kept the same in the experiment (water, cages, etc) are called the. What domain and kingdom do humans belong to? 1 opyright 2009 Pearson Education, Inc. 2 opyright 2009 Pearson Education, Inc. Outline Why study chemistry Elements Atoms, Isotopes, Periodic Table, Electrons and Bonding Bonds ovalent Bonds (Polarity), Ionic Bonds, ydrogen Bonding Water Acids and Bases hemistry Basis for studying much of biology Biology of the human body follows the rules of physics and chemistry Examples: What can cross a membrane? What biological compounds make up cells? What are the structures within the cells? What is a protein? 3 opyright 2009 Pearson Education, Inc. 4 opyright 2009 Pearson Education, Inc. hemistry Matter Anything that takes up space and has mass Elements in Nature Atoms Units of matter that cannot be broken down into simpler substances Element A pure form of matter containing only one kind of atom 5 opyright 2009 Pearson Education, Inc. 6 opyright 2009 Pearson Education, Inc. 1

2 Periodic Table of Elements Important Elements in the uman Body 7 opyright 2009 Pearson Education, Inc. 8 opyright 2009 Pearson Education, Inc. Atom Subatomic Particles omposed of parts Protons arry a positive charge (+) Neutrons arry no charge (neutral) Electrons arry a negative charge (-) 9 opyright 2009 Pearson Education, Inc. 10 opyright 2009 Pearson Education, Inc. Atom Examples of Atoms 11 opyright 2009 Pearson Education, Inc. 12 opyright 2009 Pearson Education, Inc. 2

3 Where is elium? Oxygen 13 opyright 2009 Pearson Education, Inc. 14 opyright 2009 Pearson Education, Inc. Shell Model of Electrons Number of electrons per shell 1 st shell: 2 2 nd shell: 8 3 rd shell: 8 4 th shell: 8 Where are protons found? ow many electrons can be in the 1 st shell? ow many electrons can be in the 2 nd shell? 15 opyright 2009 Pearson Education, Inc. 16 opyright 2009 Pearson Education, Inc. Periodic Table of Elements Simplified Periodic Table 17 opyright 2009 Pearson Education, Inc. 18 opyright 2009 Pearson Education, Inc. 3

4 Periodic Table of Elements Atomic Number # of protons in an atom Remember Atoms have equal number of protons and electrons It is also the number of electrons Particle Mass Proton = 1 amu Neutron = 1 amu Electron = negligible 19 opyright 2009 Pearson Education, Inc. 20 opyright 2009 Pearson Education, Inc. Periodic Table of Elements ow many electrons does Be have? Isotopes Atoms with the same number of protons but different numbers of neutrons are called isotopes 21 opyright 2009 Pearson Education, Inc. 22 opyright 2009 Pearson Education, Inc. Radioactive Isotopes 1896, enri Becquerel Rock containing uranium Marie urie (coworker) named this radioactivity Known as a radioisotope Radioactive Isotopes Radioisotopes Unstable Become more stable by emitting energy and particles 23 opyright 2009 Pearson Education, Inc. 24 opyright 2009 Pearson Education, Inc. 4

5 Radioisotopes in Medicine Isotopes in Medicine PET Scans (Positron-Emission Tomography) Image From: nutrition/way-exploit-metabolic-quirk-cancer Image From: 25 opyright 2009 Pearson Education, Inc. 26 opyright 2009 Pearson Education, Inc. Isotopes are atoms of the same element that differ in their number of. arbon has 6 protons, 6 electrons and 6 neutrons. Its atomic number is. arbon has 6 protons, 6 electrons and 6 neutrons. Its atomic weight is. a) Six b) Eight c) Twelve d) Twenty-Four 27 opyright 2009 Pearson Education, Inc. 28 opyright 2009 Pearson Education, Inc. Mass Number & Atomic Weight Atomic Weight An average of the isotopes Mass Number Atomic number Atomic weight Round the atomic weight to the nearest whole number Mass Number = (# of Protons) + (# of Neutrons) Number of Neutrons = Mass Number # of Protons Mass Number & Atomic Weight For any element # of Protons = Atomic Number # of Electrons = # of Protons = Atomic Number # of Neutrons = Mass Number Atomic Number 29 opyright 2009 Pearson Education, Inc. 30 opyright 2009 Pearson Education, Inc. 5

6 Mass Number & Atomic Weight For Be: # of Protons = Atomic Number = # of Electrons = # of Protons = # of Neutrons = Mass number Atomic Number= arbon has 6 protons, 6 electrons and 6 neutrons. Its atomic weight is. a) Six b) Eight c) Twelve d) Twenty-Four 31 opyright 2009 Pearson Education, Inc. 32 opyright 2009 Pearson Education, Inc. hemical Bonds Bonds are unions between electron structure from different atoms Molecules Same element ( 2 ) Different element ( 2 O) ompound Molecule 33 opyright 2009 Pearson Education, Inc. 34 opyright 2009 Pearson Education, Inc. Outer Shell Electrons & Bonding Full = non-reactive and stable Does not form chemical bonds Incompletely full = reactive Will form chemical bonds Number of bonds it can form depends on how many empty spots are in outer shell Don t Forget Shell Model of Electrons Number of electrons per shell 1 st shell: 2 2 nd shell: 8 3 rd shell: 8 4 th shell: 8 35 opyright 2009 Pearson Education, Inc. 36 opyright 2009 Pearson Education, Inc. 6

7 Periodic Table of Elements Review Question ow many neutrons does Li have? 37 opyright 2009 Pearson Education, Inc. 38 opyright 2009 Pearson Education, Inc. hemistry & Biology hemical Bonds 3 types ovalent Bonds Ionic Bonds ydrogen Bonds 39 opyright 2009 Pearson Education, Inc. 40 opyright 2009 Pearson Education, Inc. Strongest bonds ovalent Bonds hemical Bonds Each atom wants their outer shell filled ydrogen arbon 41 opyright 2009 Pearson Education, Inc. 42 opyright 2009 Pearson Education, Inc. 7

8 Let s look at arbon Oxygen ovalent Bonds Double Bond 43 opyright 2009 Pearson Education, Inc. 44 opyright 2009 Pearson Education, Inc. ow many bonds can carbon form? ow many bonds can hydrogen form? 45 opyright 2009 Pearson Education, Inc. 46 opyright 2009 Pearson Education, Inc. ow many bonds can helium form? ow many bonds can nitrogen form? 47 opyright 2009 Pearson Education, Inc. 48 opyright 2009 Pearson Education, Inc. 8

9 ow many bonds can oxygen form? Types of ovalent Bonds 2 atoms with unpaired electrons in the outer shell come together and share electrons Polar Nonpolar 49 opyright 2009 Pearson Education, Inc. 50 opyright 2009 Pearson Education, Inc. ovalent Bonds - Nonpolar ovalent Bonds - Polar 51 opyright 2009 Pearson Education, Inc. 52 opyright 2009 Pearson Education, Inc. ovalent Bonds - Polarity Some atoms have a greater pull on shared electrons than other atoms Electronegativity Bond between atoms with different electronegativities = polar bond ovalent Bonds - Polarity Polar ovalent Bonds Strong electrophiles (electronegative) ommon examples for biological molecules Oxygen Nitrogen Sulfur 53 opyright 2009 Pearson Education, Inc. 54 opyright 2009 Pearson Education, Inc. 9

10 ovalent Bonds - Polarity ovalent Bonds - Polarity Water O O Alcohol Ketone O O Aldehyde ydrocarbons opyright 2009 Pearson Education, Inc. 56 opyright 2009 Pearson Education, Inc. 57 ovalent Bonds - Polarity N opyright 2009 Pearson Education, Inc. 3 S 3 opyright 2009 Pearson Education, Inc. Polar Groups Oxygen ontaining arboxyl (-OO) ydroxyl (alcohol) (-O) Phosphates (-PO 4 ) arbonyl Ketone (-O) Aldehyde (-O) Nitrogen ontaining Amino (-N 2 ) Sulfur ontaining (-S) 58 arboxyl Nonpolar ompounds Alcohol 322O ydrocarbons Ketone Aldehyde Ether 3-O-23 ydrocarbons 323 opyright 2009 Pearson Education, Inc. 60 opyright 2009 Pearson Education, Inc. 10

11 ydrophilic Polar VS Nonpolar Water loving Polar Molecules ydrophobic Water fearing Nonpolar molecules ompounds hemical Formulas Write it as a formula to tell us how many atoms of each element are present Not how they molecule is put together 61 opyright 2009 Pearson Education, Inc. 62 opyright 2009 Pearson Education, Inc. 2 O ow would you draw this compound? 4 10 ow would you draw this compound? 63 opyright 2009 Pearson Education, Inc. 64 opyright 2009 Pearson Education, Inc. ow would you draw this compound? ow would you draw this compound? 4 8 O 2 65 opyright 2009 Pearson Education, Inc. 66 opyright 2009 Pearson Education, Inc. 11

12 2 4 O ow would you draw this compound? TE END for today Image From: 67 opyright 2009 Pearson Education, Inc. 68 opyright 2009 Pearson Education, Inc. 12