Honors Chemistry Chapters 2+6 – Flashcards

Contribution: Had first idea of atoms Particulars: Thought atoms were invisible and indestructible

Contribution: Said there were no atoms Particulars: 1. Said there are 4 elements: water, fire, air, earth 2. His thoughts held for about 2000 years (his ideas led to no progress in science) 3. Science became fueled by measurement i the 18th century.)

Contribution: 1. Law of conservation of mass Particulars: 1. Combustion 2. Respiration

Contribution: 1. Law of definite composition 2. Law of definite proportions (Laws are the same) Particulars: ?

Contribution: Law of multiple proportions Particulars: 1. H2O vs H2O2 2. CO vs CO2 (Dalton's Atomic Model was just a sphere/marble shaped thing with nothing in it)

Contribution: Discovers electrons Particulars: 1. Subatomic 2. Negatively charged 3. "Plum Pudding Atom" - Sphere of positive charge with electrons in the sphere like plums in a pudding 4. Charge/mass ratio = 1.76x10^8 coulombs/grams

Cathode Rays: 1. Travel in straight lines in the absence of electric or magnetic fields 2. They impart a negative charge to metals exposed to them. 3. They are made up of electrons 4. The characteristics of cathode rays DO NOT depend on the material from which they are emitted. 5. Cathode rays are deflected away from a negatively charged plate because they are negatively charged particles.

Contribution: Determines charge on an electron (through the Millikan oil drop experiment) Particulars: 1. Charge: 1.602x10^-19 coulombs 2. Mass: 9.11x10^-28 grams

Contribution: Discovers neutron (Jimmy Neutron!) Particulars: 1. Subatomic 2. Neutral charge

Contribution: Discovers the nucleus (and also the proton) Particulars: 1. Rutherford's Gold Foil Experiment 2. New model of atom: Nuclear Atom

Atoms with identical atomic numbers but different mass numbers. (Has the same number of protons but differs in the number of neutrons)

The number of protons plus neutrons in an atom. (The sum of the subatomic particles in the nucleus)

1. The number of protons in an atom of any particular element 2. Because an atom has no net electrical charge, the number of electrons it contains must equal the number of protons. (# of protons=# of electrons) (Example: Carbon has 6 protons and 6 electrons)

Electron: -1 Proton: +1 Neutron: 0

same number of protons, neutrons, and electrons

1. Radio 2. Microwaves 3. Infrared (IR) 4. Visible 5. Ultraviolet (UV) 6. X-rays 7. Gamma rays

EMR consists of photons

an individual unit of radiant energy that is most often used when referring to visible light

Higher frequency = Higher energy

Violet (Red has the least amount of energy)

Lambda

Nu

C

h

The speed is the SAME for all forms of EMR. (Travels at the speed of light) Note: Can be used to compare different forms of EMR on a test question!!!

Wavelength and frequency are inversely proportional. (As one increases, the other decreases) 1. High frequency, shorter wavelength 2. Low frequency, longer wavelength

Crest

Trough

The distance from the baseline of the wave to the crest.

The distance between two crests.

1. Energy: Joules 2. Frequency: Hertz or 1/s or s^-1 3. Wavelength: Meters

A spectrum containing radiation of all wavelengths is called a continuous spectrum. Example: Rainbows

A spectrum containing radiation of only specific wavelengths is called a line spectrum. Example: Elements can be identified by their line spectrum (???)

a simplistic model of the atom that describes the energy of an electron in terms of a particular orbit about the nucleus

The lowest energy state (n=1)

n states higher than 1 are known as excited states

f the electron in the atom makes a transition from a particular state to a lower state, it is LOSING energy.

f the electron in the atom makes a transition from a particular state to a lower state, it is GAINING energy.

Current Theory Electrons are in atomic orbitals (electron cloud)

A region in space surrounding the nucleus of an atom in which there is a high probability in finding an electron with a given amount of energy.

States that you cannot know precisely the position and momentum of an electron. 1. Wavelength of light determines accuracy 2. Short wavelength has high energy --> Moves electron 3. Longer wavelength --> Less accurate

Contribution: Energy behaves as a particle Particulars: A quantum is the smallest amount of energy that can be lost or gained by an atom

1. Treats electrons as waves 2. Quantum theory - based on the probably location of an electron 3. An orbital

1. Are solutions to Schrodinger's equation 2. Give properties of orbitals (energy, shape, orientation, and spin of the electron)

Energy N 1. Main energy level 2. n=1, 2, 3, 4, 5... 3. n=1 is closest to the nucleus

Shape 1. Shape of an orbital = sublevel 2. Shapes of orbitals are given letters s=spherical orbital - lowest energy p=dumbbell shaped d=usually 4-lobes f=usually 8 lobes

1. Naming types of orbitals 1s (1=main energy level, s=sublevel (shape) 2. Orbitals and electrons in those orbitals have defined energy. (????)

Orientation Orientation of orbital about nucleus Picture: 3 p orbitals of equal energy

Spin Two possible states of an electron in an orbital

1. orbital notation 2. electron configuration 3. condensed electron configuration 4. lewis dot structures (?)

An electron configuration or orbital diagram can be "condensed" by beginning with the nearest (before the atom) noble gas symbol in brackets to represent the core electrons, then showing the valence electrons as usual. Polonium: 54[Xe] 6s2 4f14 5d10 6p4

1. Shows only valence electrons 2. Picture them 3. Use dots for electrons

States that electrons enter into the lowest energy orbital available.

States that electrons fill equal-energy orbitals to give a maximum number of unpaired electrons. (The statement that electrons in a given sublevel remain unpaired as long as orbitals in that sublevel are empty.)

States that no 2 electrons can have the same 4 quantum numbers or... every orbital can accept only 2 electrons. (The statement that no two electrons in an atom can have the same set of quantum numbers.)

The highest sublevel of an atom (n=1, 2, 3, 4, 5)

Electrons in the highest occupied energy level of an atom

all electrons other than valence electrons

The law of constant composition

The law of multiple proportions

Excited