Chapter 2 Flashcards
Matter
anything that occupies space and has mass
Mass
amount of matter in an object
Weight
force exerted by earths gravity on matter
Element
simplest type of matter having unique chemical and physical properties
Atom
smallest particle of an element that has the chemical characteristics of that element. Only composed of one kind of atom.
-Proton
-Neutron
-Electron
Proton
positively charged atoms
In nucleus
Neutron
have no charge
In nucleus
electrons
negatively charged atoms
around nucleus in cloud
Atomic #
protons in atom (same as electrons)
Mass #
Protons + Neutrons =
Isotopes
atoms with same atomic # but different mass # (Different Neutrons)
Atomic Mass
average mass that’s naturally occurring isotopes weighted according to abundance.
Mole
substances containing Avogadros # (6.022x10^23) of atoms, icons, or molecules.
Molar Mass
mass of 1 mole of the substance in grams (g)
Chemical behavior is determined by what
outermost electrons (outer shell called Valence Shell)
Inside layers - 2, Outside layers =8
Ions
atoms that have gained or lost electrons
Cation
Positive charged, atom that loses 1 or more electrons
Anion
negatively charged after accepting 1 or more electrons
Ionic Bond
Transfer of Electrons.
attraction of oppositely charged cation and anion to each other.
Covalent Bond
Shared electrons.
Polar covalent bond
when sharing of electrons is unequal and can produce polar molecule that is electrically asymmetric.
Molecule
two or more atoms chemically combined to form a structure that acts like independent unit
Compound
two or more different types of atoms chemically combined
molecular mass
adding up atomic masses of its atoms (or ions)
Hydrogen bond
weak attraction between H+ and H- or other polar molecule. Important in determining properties of water and 3D of large molecules
Solubility
ability of one substance to dissolve in another.
Electrolytes
ionic substances (with charge) that dissolve in water by dissociation
Nonelectrolytes
molecules that do not dissociate in water
Synthesis Reaction
chemical combination of two or more substances to form a new larger substance. Small to Big.
Dehydration Reaction
synthesis reaction where water is produced
Anabolism
sum of all synthesis reactions occur in body (ATP, proteins, carbs, lips etc)
growth, maintenance, repair, can’t do without
Decomposition Reaction
chemical breakdown of a larger substance to two or more different smaller substances. Big to small.
Hydrolysis reaction
decomposition reaction in which water is depleted
Catabolism
sum of all decomposition reactions in body.
Food digestion, breakdown of fat stores, foreign matter in blood etc.
Reversible reactions
produce equilibrium condition where reactants vs products remains the same. Converted back to original.
rate of products form = rate of reverse reaction
oxidation-reduction reaction
involve complete(ionic bond) or partial transfer (covalent) of electrons between atoms
Energy
ability to do work (move matter)
Potential energy
stored energy (ball in hand at arms length)
Kinetic energy
energy resulting from movement of an object. (ball released from hand falls towards floor and back to hand)
Mechanical energy
position or movement of objects. (limb, breathing, circulating blood)
Chemical energy
- form of potential energy
- when products contain more potential energy than require the input of energy
-when products have less potential energy than reactants release energy
Heat energy
-energy that flows between objects at different temperatures
-released in chemical reactions (responsible for body temp)
Activation energy
minimum energy that reactants must have to start chem reaction
enzymes
-specialized protein catalysts that lower activation energy for chem reactions.
- speed up chem reactions but are not consumed/altered during
what increases rate of chem reactions?
increased temp & concentration
Water
polar molecule of 1 atom of oxygen, 2 atoms of hydrogen
- form hydrogen bonds
-stabilizes body temp, protects against friction/trauma, makes chem reactions possible, directly participates in chem reactions (hydrolysis/dehydration), mixing medium (solutions, suspensions, colloids).
mixture
combo of two or more substances physically blended together but not chem combined
solution
any liquid, gas or solid - uniformly distributed with no clear boundary between the substances
solute vs solvent
solute dissolves in solvent
suspension
mixture containing materials that separate from each other unless they are continually, physically blended together
colloid
mixture where dispersed (solute like) substance is distributed throughout dispersing (solvent like) substance. particles do not settle out of a colloid.
osmole
contains avogrado’s # (6.022 x 10^23) of particles (atoms, ions, molecules) in 1 kg of water
milliosmole
1/1000 of osmole
Acids vs bases - donates/accepts
Acid: Proton H+ donors
Base: OH- are proton acceptors
Strong vs weak Acid/Base
strong acid/base almost completely dissociates in water. a weak acid/base partially dissociates
Neutral Solution
H+ = OH- , pH 7
Acidic solutions
H+ > OH- , pH <7 less than
Basic or Alkaline solutions
H+ < OH- , pH > 7 greater than
salt
molecule consisting of cation other than H+ and an anion other than OH-.
salts form when acids react with bases
buffer
solution of conjugate acid-base pairs that resist changes in PH when acids or bases are added to solution
organic molecules contain what
carbon and hydrogen bound together by covalent bonds
monosaccharides
building blocks of other carbs.
Ribose, deoxyribose, glucose, fructose, galactose.
(glucose esp important)
disaccharide
molecules formed by dehydration reactions of two monosaccharides. Broken apart by hydrolysis.
Sucrose, lactose, maltose
polysaccharide
composed of many monosaccharides bound together in long chain.
-cellulose, starch, glycogen
triglycerides
composed of glycerol and fatty acids. 1,2,3 can attach to glycerol molecule
energy is stored in fats
fatty acids
straight chains of carbon with carboxyl group.
can be saturated (1 single covalent bond b/w carbon) or unsaturated (have 1+ double covalent bonds b/w carbon)`
phospholipids
lipids where fatty acid is replaced with phosphate containing molecule. phospholipids are major structural component of plasma
steroids
are lipids with four interconnected rings.
cholesterol,bile salts, and sex hormones
lipids
fat soluble vitamins, prostaglandins, thromboxjnes, and leukotrienes
building block of protein
amino acids joined by peptide bonds
what determines structure of a protein
1: #, kind, arrangement
2: hydrogen bonds b/w amino acids
3: hydrogen bonds b/w amino and water (helix)
4: interactions between protein subunits
enzymes
protein catalysts that speed up chem reactions by lowering activation energy
- active sites only bind to specific reactants
enzymes
protein catalysts that speed up chem reactions by lowering activation energy
- active sites only bind to specific reactants
- cofactors are ions/organic molecules (vitamins) that are req for some enzymes to function
Nucleotide
basic unit of nucleic acid.
-monosaccharide with an attached phosphate and nitrogenous base
- deoxyribose, adenine, thymine, guanine, cytosine.
- DNA is double strand of joined nucleotides (complementary/antiparallel)
Gene
sequence of DNA nucleotides that determine structure of a protein or RNA
RNA nucleotides
- monosaccharide ribose
-thymine of DNA is replaced with uracil
ATP (adenosine triphosphate)
stores energy from catabolism. Energy released from ATP is used in anabolism and other cell processes.
