Q2 GENCHEM

Quantum No.

theory that tells us that in an atom, the electrons are found in orbitals and each orbitak has characteristics of energy

lewis electron dot structure

shows how valence electrons are arranged among atoms in a molecuke

covalent bond

a bond formed by sharing electrons

duet rule

stable with only 2 valence electrons

octet rule

stable to have 8 valence electrons

single covalent bond

a bond formed by atoms tgat shares one pair of electron

double covalent bond

a bond formed by atoms tgat shares two pair of electron

electron domains

total number of pairs foinf in the molecule taht contribute to its shape

molecular geometry

• also known as the molecular structure

• the arrangement of atoms

• valence shell electron-pair repulsion theory (vsepr)

polar molecule

• possess several positive charges whereas the opposite has negative charges

• up to 1.8 electronegativity difference

non polar molecule

• does not have the charges present at the end

• 0 electronegativity difference

ionic

has 1.8 and above electronegativity difference

hydrocarbons

• organix molecules are based on a framework of carbon-carbon and carbon-hydrogen bonds

structural formula

unambiguously shows how the atoms are bonded togther

aliphatic

have straight branched and cyclic (ring) chaijs

saturated

single bonds thus with max no. of hydrocarbon atoms

unsaturated

double or triple bonds

aromatic

those hydrocarbons with benzene rings with six carbon atoms that form into hexagons

isomers

compounds wity the same molecular formula but different structure

functional group

grouo of atoks that replaces hydrogen atom in a hydrocarbon

monomer

a small molecule

• fatty axid

• nucleotide

• amino acid

polymer

• a long chain molecuke made uo of a repeated pattern of monomers

• most of them are hydrocarbons

addition polymerization

• known as chain growth polymerization

• when a monomer forms a hughly reactige free radical or molecule with an unpaired electron

condensation polymerization

• also oniwn as step growth polymerization

• when ywo monomers react to form a larger molecule and eliminate a smaller molecule

linear polymer

• resembles spaghetti sith long chains

branched polymers

• spaghetti with hanging chaijs

crosslinked polymer

• resemble ladders

networked polymer

reselbles piatos

heat capacity

the polymer acts as an effectual insulator against the flow of heat

thermal expansion

thebpolymer expands or contrasts when heated or cooled

crystalinity

the polymer chains are arranged in a regualr structure instead of a random fashion

permeability

the tendency of a polymer to pass extraneous materials

elastic modulus

a quantity that measures an object or substance resistance to being deformed elastically when stress is applies

tensile strength

the strength of the plastic

resilience

ability of plastic to resist abrasion and wear

refractive index

the plastic affects light as it passes through the polymer

resistance

• to electric current—insulator since most polymers do not conduct elextricity

unreactivity

most polymers are not affected by air or water

stabilizers

use to increase the ability of plastic to resist oxidation

plasticizers

increases the flexibility of plastic by acting as lubricant

macromolecule