Module 3 (Lecture) - Chemistry Flashcards
protons
positively charged, found in nucleus of atom
neutrons
neutral charge, found in nucleus of atom
electrons
negatively charged, move around nucleus
each atom carries the same number of ___ and ___
protons and electrons
vertical row of periodic table
group
horizontal row of periodic table
period
period
number of electron shells
group
number of valence electrons
__ + __ = mass number
protons + neutrons
octet rule
atoms will bond with other atoms that can compensate for their deficiency in valence electrons
molecule
two atoms physically joined together
ion
charged form of an atom
anion
negatively charged due to gain of electron
cation
positively charged due to loss of electron
ionic bond
- occurs between two oppositely charged ions
- transfer of one or more electrons so both have complete outer shells
covalent bond
at least two atoms share valence electrons to complete outer shell
polar covalent bond
unequal sharing of electrons due to the ability of one of atoms to attract electrons more strongly than the other
electronegativity
ability of an atom to attract electrons
polarity
- difference in charges within a molecule
- ex. oxygen having higher electronegativity than hydrogen, giving it a slightly negative charge
hydrophilic molecules
strongly attracted to water & dissolve easily
hydrophobic molecules
do not contain polar covalent bonds, not attracted to water, & do not dissolve easily
potential energy
stored energy
chemical energy
potential energy stored in bonds between atoms in compounds and molecules
kinetic energy
- energy associated with motion
- ex. thermal, rotational, translational
exergonic reactions
release energy and break bonds
endergonic reactions
absorb energy and form bonds
anabolic/synthesis reaction
- forms bonds
- A + B ——- AB
catabolic/decomposition reaction
- breaks bonds
- AB ——– A + B
exchange
- both anabolic and catabolic reactions
- AB + CD —— AC + BD
- AB + C ——– AC + B
reversible
- proceed in either direction
- A + B ~~~~ A + B
factors that can affect reaction rate:
concentration, temperature, energy, catalysts
compound
substance with two or more different elements
organic compound
- contain carbon atoms
- bond: covalent
- bonds to: hydrogen, nitrogen, oxygen
- ex. carbs, lipids, proteins, nucleic acids
inorganic compound
- lack carbon atoms
- bond: covalent or ionic
- ex. water, acids, bases, salts
mixture
molecules and elements mixing without forming bonds
solution
- homogenous
- solvent & solute
- transparent, particle very small (sugar in tea)
solvent
substance in which other substances dissolve
solute
substance that dissolves within solvent
colloid
- heterogenous
- large particles, translucent or cloudy (milk)
suspension
- heterogenous
- large particles, translucent/cloudy (blood)
pH scale
measures how acidic or basic by measuring concentration of hydrogen ions
acid
- pH < 7
- hydrogen > hydroxide
- strongest in body: hydrochloride (pH =2)
base
- pH > 7
- hydroxide > hydrogen
- strongest alkali pH towards 14
- proton acceptors
neutral
- pH = 7
- hydroxide = hydrogen
- ex. pure water
salt
- do not contain hydroxide or hydrogen
- acid + base —— salt + water
- contain cations & anions
carbohydrates
formed by carbon, hydrogen, and oxygen in 1:2:1 ratio
monosaccharides
- structure: monomer
- example: fruit and plant juice
- function: energy source, component of DNA and RNA
disaccharides
- structure: two monomers
- example: sucrose
- source: sugar cane and roots of sugar beet
- function: energy source & dietary source of monosaccharides
polysaccharides
- structure: 100+ monomers
- example: starch
- source: grain and potato products
- function: energy source, energy storage, blood glucose regulation, dietary source of monosaccharides
glycogenolysis
occurs when blood glucose levels fall; glycogen stores are broken down and released into the blood to bring glucose levels back to normal
glycogenesis
occurs when blood sugar levels rise; glucose taken up from blood by cells in liver and skeletal muscle and used to form glycogen
lipids
hydrophobic molecules formed by carbon, hydrogen, and oxygen
saturated fatty acid
carbon connected to at least two hydrogen atoms
unsaturated fatty acid
one or more double bonds, losing hydrogen atoms
triglycerides
- function: energy, insulation, flexibility
- structure: glycerol and three fatty acid chains (sat. or unsat.)
- example: butter and cheese
phospholipids
- function: make up cell membrane
- hydrophilic head: phosphate and glycerol
- hydrophobic tail: two fatty acid chains
steroids
- structure: four interlocking carbon rings
- function: gives cell membrane flexibility
- is precursor to Vitamin D
- high cholesterol —- heart disease
proteins
- composed of amino acid chains
- 20% of body mass
- structure: alpha carbon, carboxylic acid group, R group
essential amino acids
cannot be synthesized
non-essential amino acids
can be synthesized
protein structures
- primary: chain of amino acids
- secondary: alpha helix or beta pleated sheet
- tertiary: 3D shape depending on R group
- quaternary: several folded chains together
nucleic acids are composed of
nucleotides
nucleotide structure
phosphate group, nitrogenous base, pentose sugar
DNA base bonds
adenine & thymine
guanine & cytosine
in RNA, thymine is replaced with ____
uracil
ATP structure
ribose, adenine, 3 phosphate groups
ATP function
energy
