chem final sem 1

atoms are made of

subatomic particles (protons, neutrons, electrons)

charge of a proton

positive

charge of a neutron

no charge

charge of an electron

negative

mass of a proton

1 amu

mass of a neutron

1 amu

mass of an electron

\> 1 amu or 1/2000 amu

atomic mass

the number of protons plus + number of neutrons

atomic number

number of protons

isotope

atoms/molecules of the same element with different a number neutrons

ion

atoms/molecules of the same element with different charges

average atomic mass equation

multiply (mass x percentage) for each isotope, then add them together

does an electron jumping from lower to higher energy levels absorb or release energy

absorb

does an electron jumping from higher to lower energy levels absorb or release energy

release

aufbau principle

electrons occupy the orbitals of lowest energy first

hunds rule

every orbital in a subshell is singly occupied with parallel spins before any orbital is doubly occupied

four main electron energy levels

s (sharp), p (principle) d (diffuse) and f (fundamental)

red

color with the longest wavelength; lowest energy/frequency

violet

color with the shortest wavelength; highest energy/frequency

periods

rows on the periodic table

groups

columns on the periodic table

alkalai metals

group 1

alkaline earth metals

group 2

halogens

group 17

noble gases

group 18

metal

mostly solid (except mercury), conduct electricity

nonmetals

can be solid, liquid or gas, do not electricity

metalloids

properties of metals and non metals

valence electrons

the outermost electrons; count the number of electrons an atom or molecule has on the outer most shell

does increasing distance increase or decrease attraction

decrease

columbs law

a law stating that like charges repel and opposite charges attract

like charges

repel each other

opposite charges

attract each other

does increasing number of charges increase or decrease attraction

increase

does distance or charges have a greater effect on attraction

distance

ionization energy

the energy required to remove an electron

electron affinity

the energy required to add an electron

is stronger attraction is associated with higher or lower levels or ionization energy

higher

atomic radius trend

increases down a group, decreases across a period

ionization energy trend

increases across a period, decreases down a group

electronegativity trend

increases across a period, decreases down a group

electron affinity trend

increases across a period, decreases down a group

trend of NONMETAL reactivity

increases across a period, decreases down a group

trend of METAL reactivity

increases down a group, decreases across a period

non-metal reactivity follows the same trend as

ionization energy, electron affinity, & electronegativity

metal reactivity follows the same trend as

atomic radius

metallic bonding

metals only

ionic bonding

nonmetals and metals

covalent bonding

sharing of electrons; nonmetals and nonmetals

cations

positively charged ions

anions

negatively charged ions

ionic bond

a chemical bond resulting from the attraction between oppositely charged ions

lattice structure

a systematic, symmetrical network of atoms forming an ionic solid

lattic energy

the energy released when one mole of an ionic crystalline compound is formed from gaseous ions

formal charges

exist when an atom is surrounded by more or fewer valence electrons than it has in its neutral state

ionic character

the greater the electronegativity difference the greater the ionic character. ex: HF, covalent bonds have the least ionic character

polarity

molecules having uneven distribution of charges

polar covalent bond

unequal sharing of electrons

nonpolar covalent bond

a covalent bond in which the electrons are shared equally by the two atoms

empirical formula

the simplest whole number ratio of atoms of each element present in a compound

intermolecular forces

forces of attraction between molecules

gas IMF

weakest/none

liquid IMF

moderate, can break and interchange

solid IMF

strong, unchanging

melting point

higher IMF

london dispersion force

the intermolecular attraction resulting from the uneven distribution of electrons and the creation of temporary dipoles

dipole-dipole forces

attractions between oppositely charged regions of polar molecules

hydrogen bonding

only exists between highly polarized atoms. H can bond with only N, O & F

boiling point

the temperature where IMFs are overcome

matter

anything that has mass and takes up space; MIXTURES or SUBTANCES

mixture

material composed of two or more elements or compounds that are physically mixed together but not chemically combined

substance

matter that has a uniform and definite composition

synthesis

A+B = AB

decompostition

AB-\>A+B

single replacement

A + BC --\> AC + B

double replacement

AB + CD = AD + CB

adding numbers with sig figs

round to the least percise digit

multuplying and dividing with sig figs

round to fewest number of sig figs

mole

6.022 x 10²³ particles of an element

KHDBDCM

kilo, hecto, deca, base, deci, centi, milli

alpha particle

a helium nucleus emitted by some radioactive substances, originally regarded as a ray.

beta particle

electron with a 1- charge

positron

0/+1 e

gamma particle

0/0 y

nuclear stability

determined by the ratio of protons to neutrons in the nuclide for an isotope

transmutation

a change in the identity of a nucleus as a result of a change in the number of its protons

heavy nucleus (\> 82 protons)

fix: alpha decay

too many neutrons

fix: beta decay

too many protons

fix: positron emission

charge

protons minus electrons

ion

a charged atom

ground state

the lowest allowable energy state of an atom

excited state

a state in which an atom has more energy than it does at its ground state

isoelectronic

having the same number of electrons

s subshell

1 orbital, 2 electrons

p subshell

3 orbitals, 6 electrons

d subshell

5 orbitals, 10 electrons

f subshell

7 orbitals, 14 electrons

particles to moles

divide by 6.02 x 10^23

grams to moles

grams/molar mass