Chemistry Chapter 2 Atomic Structure Particles Proton Neutron

Chemistry Chapter 2

Atomic Structure Particles Proton Neutron Electron Charge +1 no charge -1 Mass 1 amu 0 amu

Chemical Bonds Ionic bonds: electrons are transferred Cation + Anion – Covalent bonds: electrons are shared Polar (slight charge) Nonpolar (no charge) Hydrogen bonds: (weak intramolecular bonds)

Chemical Reaction § § § Synthesis Decomposition Single Displacement Double Displacement Hydrolysis Dehydration § § § A+B C C A+B AB + C AC + B AB + CD AD + CB H 2 O + C A + B – H 2 O C

Energy Transfer § Endothermic / Endergonic – Absorption of energy § Exothermic / Exergonic – Release of energy

Rate of Reaction § Temperature – increase in temperature leads to an increase in kinetic energy (faster moving particles) § Particle Size – increased surface area allows particles to collide more frequently. § Concentration – the more concentrated a solution is, the more likely the particles will collide. § Catalysts – (enzymes) – help by lowering the amount of energy needed for a reaction to proceed. (not used up during the rxn)

Acids and Bases § p. H scale (0 – 14) (measures the hydrogen ions in a soln) § Acid (sour taste; corrosive) § molecule capable of releasing H+ § molecule that absorbs a OH- § Base (bitter taste; slippery) § molecule capable of absorbing H+ § molecule that releases a OH- § Titration – balancing acid and base

Salts § Formation of a salt § HCl + Na. OH –> H 2 O + Na. Cl § Salt is an ionic compound that contains cations other than H+ and anions other than OH -

Buffers § Buffer - a substance that either releases or absorbs H+ and helps to prevent a drastic change in p. H. § When the buffer runs out the p. H will again begin to fall with the addition of more H+.

Carbohydrates Monosaccharides – simple sugar (single chain or ring) ex: glucose, galactose, fructose Disaccharides – double sugar ex: sucrose, lactose, maltose Polysaccharides – many sugars ex: starch, glycogen, cellulose,

Lipids § Fats, Oils, Waxes § Higher number of C – H bonds than carbohydrates § Used for Lubrication, Waterproofing, Insulation, Energy Storage § Saturated vs. Unsaturated § Phospholipids, Steroids, Triglycerides

Proteins § Composed of 20 different amino acids. (vary by the side chain: R-group) § What makes one protein different from another is the amino acids making it up and the order of the amino acids. Each amino acid has an amine group (-NH 2) and a carboxyl group (-COOH)

Protein Formation Peptide bond formation: long chains of amino acids joined by a dehydration reaction Proteins are classified based on function. § Folding of proteins creates different structures: primary, secondary, tertiary, quaternary Proteins can form bonds with themselves or other proteins

Protein Classification 2 ways of classifying proteins Structural Protein – fibrous proteins; composed of intertwined chains, resembles a rope, used for support, insoluble (ex: collagen) Functional Proteins – globular proteins; compact and spherical, water soluble, chemically active, mobile (ex: antibodies, enzymes, and protein-based hormones)

Protein Denaturation Denaturing – heat or p. H effects hydrogen bonds in a globular protein and can permanently change it Denaturation destroys active sites ex: hemoglobin becomes unable to bind and transport oxygen when blood p. H is too high

Molecular Chaperones § Globular proteins that prevent incorrect folding, help move certain ions across cell membranes, break down damaged/denatured proteins, etc. § Ex: stress proteins- produced in response to traumatizing stimuli

Enzymes § Globular proteins that act as catalysts § They regulate and accelerate biochemical reactions § Each enzyme is chemically specific

Nucleic Acids § DNA § Found in the nucleus § Blueprint of life (CGAT) § Inheritable § RNA § 3 types § m. RNA (messenger) § t. RNA (transfer) § r. RNA (ribosomal) § Single Stranded § Uracil replaces thymine § ATP § Adenosine triphosphate § energy