H Chem: Unit 3

c=3.00 x 10⁸ m/sec

lamda, nm; the distance from crest to crest of adjacent waves

nu, Hertz; the # of waves that pass through a point per unit of time

v, m/sec

E, Joules (J)

h=6.626 x 10^-34 Jsec

• can move a lot because they're almost massless
• have properties of waves and can be measured like them

electrons have two behaviors, of particles and waves

• small wave=little energy
• big wave=a lot of energy

height of the wave from the baseline to the crest

the line that crosses the waves horizontally that divides it equally up and down

• lowest frequency=longest wavelength
• highest frequency=shortest wavelength
• inversely related

• a mneumonic device for memorizing the colors of the visible electromagnetic spectrum
• red orange yellow green blue indigo violet

describes the range of energy that does not need a medium to travel through

• describe how electrons fit in atoms and how they are arranged
• represent an aspect of electrons' positions, but only describes the nature

• principle quantum number (n)
• angular momentum quantum number (l)
• magnetic quantum number (m)
• electron spin quantum number (s)

describes energy levels, can range from 1-7 like the periods

• low energy level will be small, close to the nucleus, and low in energy
• high energy level will be large, further from the nucleus, and higher in energy

speed of light, c

electrons further from the nucleus will have more energy

describes the shape of orbitals, that each energy level can be made up of s, p, d, and/or f

• s= one
• p= three
• d= five
• f= seven

use the periodic table, the energy level corresponds to the period, and you can see which blocks (s, p, d, f) are included in which periods, and you know how many orbitals represent each layer

• s= 2e
• p= 6e
• d= 10e
• f= 14e

two

stream of tiny packets of energy

longer wavelengths=lower photon energy

probability map for an electron, decreases as the electron gets further away from the nucleus

• synonymous with principle quantum number (n) and angular momentum quantum number (l)
• there are seven energy levels, and these are divided into certain shapes of oritals

• s= sphere
• p= double lobe
• d= clover (double, double lobe)
• f= multiple wacky shapes

describes their orientation in space, how it is arranged in 3D

• describes the spin of the electron in its shape cloud; in each shape cloud there are 2 electrons, and they have equal but opposite movement
• spin values are +1/2 and -1/2, means up/down

s and p

# of valence electrons

• for any s or p blocks, n=row#
• for d block, n=row-1
• for f block, n=row-2

vacuums

• find the previous noble gas, put its symbol in [brackets], then configure from its point on
• this can show you the number of valence electrons (associated with highest n)

• a given compound always contains the same proportions (by mass) of the elements
• elements will always be in the same ratio/composition

• elements are made of atoms
• all atoms of a give element are identical
• the atoms of one element differ from the atoms of a different element
• atoms of different elements combine to form compounds, consistent in composition
• atoms don't break up in chemical processes, no atom is created nor destroyed

predict how a pair of elements could form different kinds of compounds

• found electrons and reasoned that there must be positive particles as well
• known for finding electrons

• plum pudding model of the atom, uniform composition, enough positive and negative particles to balance out the charge
• known for his plum pudding model

• found positively charged alpha particles
• did the beam test and found that they bounced off of a thin metal at different angles
• reasoned that the positive particles were small and in the center, dense, and the rest was empty space
• known for finding neutrons

Rutherford's name for an atom with a dense center of positive charge (nucleus), with electrons around it and empty space

• protons and neutrons in the small center, surrounded by electrons and a lot of empty space
• charge of atom is balanced and electrons move around the nucleus

• hydrogen has a small positive nucleus with electrons orbiting it
• thought there were energy levels like rings
• thought electrons could jump from levels by emitting or absorbing photons of energy

light has wave and particle characteristics, and so do electrons

• electrons are in orbitals that do not precisely describe the electrons' movements/paths
• shows the probability of where electrons go

Democritus described matter in terms of atoms which were indivisible

• each substance has its own chemical formula, definite formula
• e.g. H₂O, all water has this ratio

• elements may combine in various proportions with each other
• e.g. water and oxygen can combine like H₂0 or H₂O₂

unstable, unmaintainable state of electrons after photon absorption

normal energy state of electrons

• a spectrum that represents a continuous array  of energy throughout mediums, no blank spots
• e.g. the electromagnetic spectrum

the colors that you see being bounced off, the thin slices of energy that are not asborbed

electrons in the outermost energy level

positive ions, never negative ions

• group 1A- +1 ions
• group 2A- +2 ions
• group 3A- +3 ions
• group 4A- unpredictable
• group 5A- -3 ions (except metals)
• group 6A- -2 ions
• group 7A- -1 ions
• group 8A- noble gases, very stable

electron cloud

use shorthand electron configuration method, count all of the electrons in the highest energy level

ds

known for Dalton's atomic theory, and the idea that elements are made up of indivisible atoms

in angular momentum quantum numbers, electrons fill up orbitals and THEN they pair up, so unpaired electrons are electrons in orbitals which are alone

an atomic orbital can hold a maximum of 2 e-s, and those electrons have opposite spins

• full or half full orbitals
• energy levels with more electrons

electron(s) will jump from a previous orbital into the next orbital, the second to last orbital will be missing an electron and it will be in the next spot(s)

atoms with the same number of electrons and therefore the same configurations

the quantity of energy required to remove an electron from the gaseous atom or ion

metals

atomic radius, how large the atom is, the measurement of a line drawn between of the two centers of atoms

freezing something in a gaseous state so that it will turn into a solid and you can measure fixed points (in the nucleus)

• as you move from top to bottom, atomic radius increases
• number of energy level increases and therefore outermost e-s are further from nucleus

• as you move from left to right (across a period), atomic radius decreases
• atomic number increases and the larger number of protons increases the atom's ability to hold e-s close so atomic size decreases

the amount of energy required to remove one, two, three, etc. electrons in succession from an atom

• as you move from top to bottom in a group, first ionization energy decreases
• electrons close to the nucleus are harder to remove because the nucleus pulls them more, and electrons get further away from the nucleus with higher energy levels

• as you move from left to right (across a period), ionization energy generally increases
• as the number of valence electrons increases, it becomes better to just add electrons than to subtract them in order to achieve a full or half full valence orbital status

LLL- larger lower left

pattern not true when an element could be full or half full, or having just one full letter orbital

• electrons closer to the nucleus shield outer electrons from nuclear forces, the attraction of the nucleus is shielded
• therefore it is easier to remove electrons in the outer orbitals and ionization energy is less

the attraction of an atom fro the electrons of another atom

Fluorine, only needs one more electron to fill its valence orbital and it has a small energy level so shielding does not take effect

the size of the ion

negative ions are bigger than positive ions in general

increases across a group (from left to right) and decreases from top to bottom

higher frequency = higher energy

any form of energy in the electromagnetic spectrum that travels at the speed of light

colors

ground

released

more energy in 2s, further away from nucleus, bigger

one orbital, can hold up to 2 e-s, spherical shape