Unit 1 - Chapter 2 Flashcards
Atom
The basic unit of chemical element
Element
A pure substance that cannot be simplified or broken down further
Protons
1amu
(+1)
Located in the nucleus
Neutrons
1.008amu
Neutral
Located in the nucleus
Electron
0.0005486amu
(-1)
Orbitals (outside nucleus)
Isotopes
Varieties of elements that differ only in the number of neutrons.
Atomic Number
The number of protons in the nucleus of an atom
Atomic Mass
The mass of an atom – approx. equal to the number of protons & neutrons
How is the Periodic Table Organized
Rows (Periods)
Columns (Groups)
Arranged in order of increasing atomic number.
Atom Stability
Atom Stability – balanced state where the forces in the nucleus are evenly distributed (*Primarily protons and neutrons)
Octet Rule
tendency of atoms to have 8 electrons in the valence shell (preferred)
Molecular Formula
The number of atoms of each element present in one molecule of a specific compound
Structural Formula
graphic representation of a specific molecular structure
Covalent Bonds
Bonds between atoms that share electrons
Nonpolar Covalent Bonds
electrons shared equally
Polar Covalent Bonds
electrons shared unequally
Properties of water - polarity
Uneven distribution of electrical charge within a water molecule
Properties of water - hydrogen bonding
electrostatic attraction between slightly positive hydrogen atoms of a water molecule and the slightly negative oxygen atom of a closely neighboring water molecule. Creates weak intermolecular force that holds water molecules together.
Properties of water - solvency
Ability to dissolve polar or ionic substances.
Solute
a dissolved substance (smaller amounts than solvent)
Solvent
substance with the ability to dissolve other substances (forms a solution)
Solution
particles of matter (solutes) mixed with more abundant substances (solvent)
Define the ionization of water
Chemical reaction that occurs when water molecules donate protons to one another forming hydronium and hydroxide ions.
pH
(potential of hydrogen) measure derived from the mobility of H+
1) 7.0 is neutral.
2) Less than 7 is an acidic solution.
3) Greater than 7 is a basic solution.
Acid
substance that releases hydrogen ions when dissolved in water (Proton donor)
Base
substance that can accept hydrogen ions (protons) in a solution (proton acceptor)
Buffer
chemical system in the body that helps maintain stable pH. Neutralizes hydrogen and hydroxide ions
Inorganic Compound
Substance that does not contain both carbon and hydrogen
Organic Compound
Chemical compound that contains Carbon/Carbon or Carbon/Hydrogen bond
Hydroxyl
(-OH)
Methyl
(-CH3)
Amino
(-NH2)
Carboxyl
(-COOH)
Phosphate
(-H2PO4)
List the three major monosaccharides
Glucose, Fructose, Galactose
List the three major disaccharides and the monosaccharides that make them
-Sucrose – Glucose & Fructose
-Lactose – Glucose & Galactose
-Maltose – Glucose (2)
Define a Polysaccharides and give two
Carbohydrate whose molecules consist of a number sugar molecules bonded together. i.e starch, cellulose
Define saturated fatty acid
Chains of 4-24 carbon atoms with carboxyl group on one end and methyl group on the other
Define unsaturated fatty acid
Contain some double bonds between carbons in chain
List the molecules that make up the triglyceride
Glycerol & 3 Fatty acids
List the molecules that make up the phospholipid. Where do you find phospholipids?
Glycerol, 2 fatty acids, phosphate group and alcohol
Phospholipids are found in the cell membranes of all living things
Distinguish between the polar and nonpolar ends of a phospholipid and the solubility differences.
Polar has a “head” that readily interacts with water (Hydrophilic) – Are partially water soluble
Nonpolar has a “tail” that made of fatty acid chains that avoid water (Hydrophobic) – Are not water soluble
Define steroids and list two common steroids
Cortisol & Cholesterol
Amino Acid
Central carbon with 3 attachments
Peptide Bond
Joins amino group of 1 amino acid to the carboxyl group of the next
Describe the importance of structure in proteins.
It directly determines its function – how it interacts with the body
Denaturation
Extreme conformational change that destroys function.
i.e. extreme heat or pH
Primary Protein Structure
1 Amino chain
Covalent and Peptide bonds
Linear Chair
Non-Functional
Secondary Protein Structure
1 Amino Chain
Hydrogen bonds
Coiled/folded
Non-Functional
Tertiary Protein Structure
1 Amino Chain
Disulfide, hydrogen, ionic bonds
Globular, Fibrous
Functional
Quaternary Protein Structure
2+ Amino Chains
Hydrogen bonds
Tetrahedrally Shape
Non-Functional
