Basic Chemistry Matter and Energy Matter anything that
Basic Chemistry
Matter and Energy Matter – anything that occupies space and has mass (weight) Energy – the ability to do work Chemical- energy stored in bonds Electrical- energy from movement of particles Mechanical- directly involved in moving matter Radiant-travels in waves (heat, light, x-rays)
Composition of Matter Elements Fundamental units of matter 96% of the body is made from four elements Carbon (C) Oxygen (O) Hydrogen (H) Nitrogen (N) Atoms Building blocks of elements
Atomic Structure Nucleus Protons (p+) Neutrons (n 0) Outside of nucleus Electrons (e-) Figure 2. 1
Identifying Elements Atomic number Equal to the number of protons that the atoms contain Atomic mass number Sum of the protons and neutrons
Isotopes and Atomic Weight Isotopes Have the same number of protons Vary in number of neutrons Figure 2. 3
Isotopes and Atomic Weight Atomic weight Close to mass number of most abundant isotope Atomic weight reflects natural isotope variation
Radioactivity Radioisotope Heavy isotope Tends to be unstable Decomposes to more stable isotope Radioactivity Process of spontaneous atomic decay
Molecules and Compounds Molecule – two or more like atoms combined chemically Compound – two or more different atoms combined chemically
Chemical Reactions Atoms are united by chemical bonds Atoms dissociate from other atoms when chemical bonds are broken
Electrons and Bonding Electrons occupy energy levels called electron shells Electrons closest to the nucleus are most strongly attracted Each shell has distinct properties Number of electrons has an upper limit Shells closest to nucleus fill first
Electrons and Bonding involves interactions between electrons in the outer shell (valence shell) Full valence shells do not form bonds
Inert Elements Have complete valence shells and are stable Rule of 8 s Shell 1 has 2 electrons Shell 2 has 10 electrons 10 = 2 + 8 Shell 3 has 18 electrons 18 = 2 + 8 Figure 2. 4 a
Reactive Elements Valence shells are not full and are unstable Tend to gain, lose, or share electrons Allows for bond formation, which produces stable valence Figure 2. 4 b
Chemical Bonds 3) IONIC BONDS a) Form when electrons are completely transferred from one atom to another 4)IONS a) Charged particles i)Anions are negative ii) Cations are positive iii)Either donate or accept electrons
Chemical Bonds 5) COVALENT BONDS a) Atoms become stable through shared electrons b) Single covalent bonds share one electron c) Double covalent bonds share two electrons Figure 2. 6 c
Examples of Covalent Bonds Figure 2. 6 a–b
Polarity- unequal sharing of e 8) OCCURS IN COVALENTLY BONDED MOLECULES a) Some are non-polar i)Electrically neutral as a molecule b) Some are polar i) Have a positive and negative side Figure 2. 7
Chemical Bonds 9) HYDROGEN BONDS a) Weak chemical bonds b) Hydrogen is attracted to negative portion of polar molecule c) Provides attraction between molecules d) Important for i) properties of H 2 O ii)3 -D structure of proteins iii) holding DNA strands together
Patterns of Chemical Reactions 11)SYNTHESIS REACTION (A+B AB) a) Atoms or molecules combine b) Energy is absorbed for bond formation 12) DECOMPOSITION REACTION (AB A+B) a) Molecule is broken down b) Chemical energy is released
13)Synthesis and Decomposition Reactions Figure 2. 9 a–b
Patterns of Chemical Reactions 14) EXCHANGE REACTION (AB+C AC+B) a) Involves both synthesis and decomposition reactions b) Switch is made between molecule parts and different molecules are made Figure 2. 9 c
15) Biochemistry: Essentials for Life 16) ORGANIC COMPOUNDS a) Contain carbon b) Most are covalently bonded c) Example: C 6 H 12 O 6 (glucose) 17) INORGANIC COMPOUNDS a) Lack carbon b) Tend to be simpler compounds c) Example: H 2 O (water)
18) Important Inorganic Compounds 19) WATER a) Most abundant inorganic compounds b) Vital properties i) High heat capacity ii) Polarity/solvent properties iii) Chemical reactivity iv) Cushioning
20) Important Inorganic Compounds 21) SALTS a) Ionic compounds b) Dissociate into ions in water c) Vital to many body functions d) Include electrolytes which conduct electrical currents
Important Inorganic Compounds 22) ACIDS a) Can release detectable hydrogen ions 23) BASES a) Proton acceptors 24) NEUTRALIZATION REACTION a) Acids and bases react to form water and a salt
25) p. H 26) MEASURES RELATIVE CONCENTRATION OF HYDROGEN IONS [H+] a) p. H 7 = neutral b) p. H below 7 = acidic c) p. H above 7 = basic d)Buffers: chemicals that can regulate p. H change Figure 2. 11
27)Important Organic Compounds 28) CARBOHYDRATES a) Contain carbon, hydrogen, and oxygen b) Include sugars and starches c) Classified according to size i) Mono/saccharides – simple sugars ii) Di/saccharides – two simple sugars joined by dehydration synthesis iii) Poly/saccharides – long branching chains of linked simple sugars
Carbohydrates Figure 2. 12 a–b
Carbohydrates Figure 2. 12 c
Important Organic Compounds 29) LIPIDS a) Contain carbon, hydrogen, and oxygen i) Carbon and hydrogen outnumber oxygen b) Insoluble in water- do not dissolve i) Oil in salad dressing c) Hydrophobic- water hating
Lipids 30) COMMON LIPIDS IN THE HUMAN BODY a) Neutral fats (triglycerides) i) Found in fat deposits ii) Composed of fatty acids and glycerol iii) Source of stored energy
Common Lipids IN THE HUMAN BODY (CONTINUED) b) Phospholipids i) Form cell membranes
Common Lipids IN THE HUMAN BODY (CONTINUED) c) Steroids i) Include cholesterol, bile salts, vitamin D, and some hormones Figure 2. 14 a–b
Cholesterol a) The basis for all steroids made in the body Figure 2. 14 c
Important Organic Compounds 32) PROTEINS a) Made of amino acids i) Contain carbon, oxygen, hydrogen, nitrogen, and sometimes sulfur 33) ACCOUNT FOR OVER HALF OF THE BODY’S ORGANIC MATTER a) Provides for construction materials for body tissues b) Plays a vital role in cell function c) ACT AS ENZYMES, HORMONES, AND ANTIBODIES
Proteins are made of Amino Acids 20 different amino acids Vary by R group- gives chemical character
Proteins have different 3 -D structures Based on sequence of amino acids Levels Primary- sequence Secondary- twist or pleats Tertiary- folding together Quarternary-subunits associate
34) Enzymes a) Act as biological catalysts b) Increase the rate of chemical reactions Figure 2. 17
Important Organic Compounds 35) Nucleic Acids a) Provide blueprint of life b) Nucleotide bases i) A = Adenine ii) G = Guanine iii) C = Cytosine iv) T = Thymine v) U = Uracil c) Make DNA and RNA
Nucleic Acids 36) Deoxyribonucleic acid (DNA) a) Organized by complimentary bases to form double helix b) Replicates before cell division c) Provides instructions for every protein in the body Figure 2. 18 c
Important Organic Compounds 37) Adenosine triphosphate (ATP) a) Chemical energy used by all cells b) Energy is released by breaking high energy phosphate bond c) ATP is replenished by oxidation of food fuels
Adenosine Triphosphate (ATP) Figure 2. 19 a
38) How ATP Drives Cellular Work Figure 2. 20
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