Atoms, Molecules, Ions, Acids, Bases, Buffers, pH

General Chemistry Terms

• See pgs. 26-41

• Chemistry:–Science that deals with structure of matter

–Refers to the physiology side of this class

• Matter: 3 types (solid, liquid and gas)

Atoms•Atom:

–Smallest stable unit of matter

•Three subatomic particles:–Protons:–Neutrons:–Electrons:

Atoms (continued)• Can you calculate the number of

protons, neutrons and electrons for ANY element on the periodic table?

• REMEMBER:• Protons = Atomic #• Electrons = # of protons• Neutrons = Atomic Mass # minus

Atomic #• If protons are not equal to electrons the

atom is now known as an ion• Cation = (+) and Anion = (-)

Chemical Bonds• Remember how to bond various

atoms with other atoms???? • The bonding capability is based

on the Group Number found at the top of each of the columns on the periodic table

• REVIEW the charges associated with each group. Remember that the 8th group is the most STABLE

Chemical Bonds (continued)

•Three types of chemical bonds:–Ionic bonds: between ions–Covalent bonds: shared electrons

–Hydrogen bonds: between two molecules

Inorganic Compounds• Nutrients: essential elements and molecules

normally obtained through diet• Metabolites: all molecules that can be processed

and broken down by chemical reactions in our bodies– Organic compounds:

• C and H form basis – Inorganic compounds:

• Usually do NOT contain C and H atoms as primary structure

• Most important in body:– Carbon dioxide (CO2)– Oxygen (O2)– Water (H2O)– Inorganic acids, bases and salts

Inorganic Compounds (continued)

• Water accounts for most of your body weight.

• Proteins, the key structural and functional components of cells, and nucleic acids, which control cell structure and function, work only in solution with the UNIVERSAL Solvent known as Dihydrogen oxide (water).

Acid/Base Terminology and the pH (parts per Hydrogen) Scale

• Hydrogen ions (H+) = “Chemical Bad Boy”– Highly reactive

• Break chemical bonds• Change shape of complex molecules• Disrupt cell and tissue functions

– Must be regulated precisely

• pH: concentration of H+ ions in body fluids• pH Scale: 0-14

– Neutral: solution with pH of 7– Acidic: solution with pH below 7– BasicBasic: solution with pH above 7

pH of pure water = 7

pH of blood = 7.35-7.45

Blood pH• pH of blood = 7.35-7.45• QUICK QUIZ: So is blood neutral, acidic

or basic?– Basic or otherwise known as ALKALINE!

• Large changes in pH of blood can be damaging to cells, tissues and functioning– Acidosis: low blood pH (below 7.35)

• Below 7 = coma

– Alkalosis: high blood pH (above 7.45)• Above 7.8 = uncontrollable, sustained skeletal muscle

contractions

Acids, Bases and Buffers…oh my!• Acid: “proton donor”

– Solute that releases H+ ions in solution– Lowers pH of solution– Example: HCl – hydrochloric acid; in stomach to

break down food• Base: “proton acceptor”

– Solute that removes H+ ions from solution– Example: NaOH – sodium hydroxide; Drano, lye

• Buffer:– Compounds that stabilize pH of a solution by

removing or replacing H+ ions– Weak acids and bases– Help maintain pH of body fluids within normal limits– Example: Antacid (Alka-Seltzer) – NaHCO3 (sodium

bicarbonate, baking soda)

BIOCHEMISTRY

Living things are mainly composed of four kinds of MACROMOLECULES: Proteins, Nucleic Acids, Carbohydrates and Lipids.

PROTEINS• Structurally helps build

certain areas of the body that need extra toughness or strength such as Keratin in nails and hair or cartilage.

• Chemical messengers to keep the brain in contact with the rest of the body.

NUCLEIC ACIDS• Stores information and considered

the body’s blueprint.

• Comes in two varieties, DNA or RNA

Carbohydrates• Provide energy storage• Simple carbs are known as

monosaccharides or sugars• Complex carbs are known as

polysaccharides or starches

• Composed of Carbon and Water.

LIPIDS• Long term storage otherwise known as fat• Composed of fatty acids and glycerol• Saturated fat= has single carbon bonding

•Unsaturated fat=

has double bonded carbons

THE END