Chapter 10 Chemical Compounds Ionic Compounds –Formed by oppositely charged ions –Metal and nonmetal –Properties Brittle Crystal lattice High melting point Many dissolve easily in water and can conduct electricity Covalent Compounds –Formed by sharing electrons between atoms –Nonmetals only –Properties Most do not dissolve in water but will not conduct electricity Low melting points Weaker bonds than ionic

Section 2 Acids, Bases and Salts Acids –Any compound that increases the amount of H+ (hydrogen ions) when dissolved in water –Properties Sour taste (lemon juice) Conduct electricity when dissolved Change color of some substances (turns blue litmus paper red) Acids react with metals to produce hydrogen gas (bubbles)

Bases –Any compound that increases the amount of hydroxide ions (OH-) –Properties Bitter taste (soap) Slippery feel Changes the color of some substances (turns red litmus paper blue)

pH scale Neutral acidity milk ACID BASE soda Lemon juice Laundry Detergent ammonia Sea water

Weak Vs Strong Weak acids –Only some of the acids break apart in water to form Hydrogen ions Citric acid (from oranges), carbonic acid (from soda) Strong Acids –All of the acid molecule break apart in water to form ions Sulfuric, nitric, hydrochloric acids Weak bases –Only some of the base molecules break apart in water to form hydroxide ions Ammonia Strong bases –All of the base molecules break apart in water to form hydroxide ions Sodium hydroxide (NaOH) Acids can be used to neutralize bases.

Acid + Base = Salt + H 2 O Acids produce excess hydrogen ions (H+ ) Bases produce excess hydroxide ions (OH-) Together these ions recombine back into H 2 O Any ionic compound formed by combining a base with an acid is called a salt –A–A Salt is the positive ion left from a base and the negative ion from an acid NaOH + HCl NaCl + H 2 O + - Neutralization reaction

Chapter 11 The Chemistry of Living Things Chemistry can be divided into two categories –O–Organic Chemistry (90%) Involves covalent compounds based on the element CARBON All living things makes these, are made of these and must have them to survive It is possible to create organic compounds without living things –I–Inorganic Chemistry (10%) Everything else (all other compounds)

Organic Compounds Ch. 11

Organic Compounds are made of covalently bonded Carbon molecules 4 important organic molecules are: –Carbohydrates –Proteins –Lipids –Nucleic Acids

Other Compounds Important to Living Things Water ( H 2 O) (70% of a human is H 2 O, same percent as is covering the Earth) –R–Regulates body temperature –T–Transports substances through the cells of a living thing –P–Provides lubrication Salt (NaCl, KI, CaSi, MgO, etc) (0.5% of your blood is salt, same concentration as in seawater) –H–Helps nerves conduct electricity –H–Helps regulate amount of water in a living thing All living things require these to remain consistent and balanced.

Organic Compounds Organic compounds contain carbon Organic Compounds make up 90% of all substances –C–Carbon atoms can form four bonds (only atoms that can do this) –F–Forms the molecules that make up all living things (called biochemicals ) Other important elements hydrogen, oxygen, phosphorus, nitrogen and sulfur C

Carbon Backbones Straight chains –C–Cellulose (plant fiber) Rings H- -H Branched chains –G–Glycogen supplies energy in animals –A–Aromatic hydrocarbons (air fresheners, deoderants) H - C - C - C- C- C- H H- -H H - C - C - C- C- C- H H- -H H- - C- H H- -H Carbon atoms have four valance electrons for making bonds. Carbon- based molecules have three main shapes forming the backbone of many different organic molecules.

Single Bonds- one pair of shared electrons –Fuels like propane, methane and petroleum react easily Double Bonds- two pairs of shared electrons –Many fats and oils are harder to burn Triple Bonds- three pairs of shared electrons –Acetylene (welding torches) burns only at a very high temperature H – CEC – H H- C=C H - C- C- C- H H- -H

Biochemicals Organic compounds made by living things Carbohydrates –O–One or more simple sugars bonded together – used for energy and to store energy Starch Sugar

Biochemicals Organic compounds made by living things Lipids –Stores energy and important nutrients and makes up cell membranes Fat Oil Wax

Proteins –C–Composed of amino acids There are 20 different amino acids known All living things are composed of those –R–Regulate chemical activities, transports and stores chemicals, provides structure Most living things are made of proteins Hormones Enzymes

Nucleic acids –Largest biochemical, these contain information and help build proteins DNA contains the blueprints to living things RNA actually build one small part of the protein

Carbon can form bonds with 4 atoms at once. Carbon forms 3 different shapes or “backbones” –Straight chain –Branched chain –Ring Carbon forms 3 types of bonds –Single –Double –triple

Hydrocarbon –C–Composed of only hydrogen and carbon –M–Most fuels are hydrocarbons Gasoline (C 8 H 18 ) Octane Methane(CH 4 ),Propane (C 3 H 8 ), Butane (C 4 H 10 ) –S–Styrofoam (polystyrene) –P–Plastic

C C CC CC H H H H H H Aromatic Hydrocarbons –Form rings of carbon atoms called benzene rings –Often have strong odors and are used in “smelly” products Deodorant, moth balls, air fresheners