Chemistry Final Semester 2

matter

anything with mass and volume

physical properties

properties that can be measured or observed without changing the identity of the substance

chemical properties

properties that indicate how a substance reacts with other substances chemically

physical change

a change in the physical appearance of a substance without changing it chemically

chemical change

(reacting) when substances react to form new substances

homogenous mixture

a mixture with no uniform composition in which parts cannot be picked out

heterogenous mixture

a mixture with a uniform composition in which parts can be piked out

pure substances

substances with a uniform and definite composition, either as an element or compound

Kinetic Theory of Matter

matter is made of tiny particles that are constantly and randomly moving

examples of physical properties

color, texture, odor, taste, density, mass, freezing/melting point, etc.

how to determine if a physical change has been made

if the state of matter is different

examples of chemical properties

flammability, combustibility, burn ability, etc. often associated with “reacts with”

how to determine if a chemical change has been made

if there is a change in the properties such as rusting, corrosion, and decay

describe solids

definite volume, definite shape, non-compressible, high density

describe liquids

definite volume, in-definite shape, non-compressible, less dense than solids but more dense than gases

describe gases

in-definite volume, in-definite shape, compressible, low density

four rules of sig figs

(1)non-zero numbers are sig figs (2) no leading zeros (3) tailing zeros only after a decimal (4) captive zeros are sig figs

equation for percent error

% error= | (expected-experimental) | / expected x 100

how do you multiply/divide with sig figs

the answer is rounded to the same # of sig figs as the number with the least sig figs

how do you add/subtract with sig figs

the answer is rounded to the same # of decimal places as the number with the least in the calculation

memorize the triangle ok

ok

who was Democritus

greek philosopher / first to think of the existence of atoms, believed tat matter was made of very small particles

what were the points to Daltons theory

A) All elements are made of indivisible particles (X) B) Atoms of the same element are the same in composition and mass (X) C) Atoms can combine only in whole number ratios (Y) D) Chemical reactions occur when elements join, separate, or rearrange (Y)

what did Thomson do

discover electrons

what did rutherford do

discover the nucleus

what did bohr do

study hydrogen, discover the bohr model

what is the equation to determine the average atomic mass of an atom and its isotopes

(% abundance 1)(atomic mass 1) + (% abundance 2)(atomic mass 2) +...../100

heisenburn principle of uncertainty

you cannot know both the position and speed of a particle

pauli excursion principle

it is not possible to have all identical quantum numbers

aufbau principle

electrons fill the lowest sublevel available then fill larger sublevels

hunds rule

each orbital in a sub-shell is filled once before more electrons are added

orbital diagram

a type of notation that illustrates an atom's electron distribution and electron spin within orbitals O OOO O

s sublevel

1 orbital, 2 electrons, spherical orbitals

p sublevel

3 orbital, 6 electrons, dumbell orbitals

d sublevel

5 orbital, 10 electrons, clover orbitals

f sublevel

7 orbital, 14 electrons, double clover orbitals

relationship between frequency and wavelength

higher frequency = smaller wavelength

relationship between energy and frequency

higher frequency = higher energy

equation for finding the energy of a photon

E = h (c/λ)

equation for finding the energy in an energy level

E = -(Rhc) / n^2

highest frequency of the electromagnetic radiation spectrum

gamma rays

lowest frequency of the electromagnetic radiation spectrum

radiowaves

electronegativity

tendency of an atom to take electrons

ionization energy

tendency of an atom to lose electrons

atomic radius

distance between the nuclei of two touching atoms / 2

shielding effect

a reduction of nuclear charge due to a difference in attraction force on the atom’s electrons

look here

k

ionic bonding

bonding between metals and nonmetals where they trade electrons, they form crystalline structures

covalent bonding

bonding between nonmetals where they share electrons

formula unit

the chemical formula of an ionic compound that lists the ions in the lowest ratio that equals a neutral electrical charge

empirical formula

simplest whole number ratio of atoms present in a compound

molecular formula

true whole number ration (multiple of the empirical)

types of chemical reactions

combination, decomposition, single-replacement, double-replacement, and combustion