Big Idea #1: Atoms, Elements, and Building Blocks of Matter

measurement of single atom electrons

1 eV= 1.6 • 10^-19 Joules.

all energy levels

1 s, 2 s p, 3 s p d, 4 s p d f

period trends have 3 basic rules

1. electrons attracted to protons a. closer to nucleus = stronger attraction b. more protons = stronger attraction. 2. electrons are repelled by each other so if other electrons are btwn valence electrons and nucleus the valence will b less attracted to nucleus this is shielding. 3. completed shells are very stable and atoms will + or - valence electrons to create complete shell for charge of 0

1 mole of carbon atoms has mass of

12 g/mol = 12 amu

electron configuration for nickel

1s22s^22p^63s^23p^63d^84s^2

determine electron configuration of sulfur

1s^22s^22p^63p^63s^23p^4

p subsehll energy level compared to s subshell

3 times higher because more electrons in subshell

1 mole =

6.02 x 10^23

frequency and wavelength relationship with energy

E=frequency/wavelength. inversely proportional. higher freq = more energy

Energy and Electromagnetic Radiation relationship

E=hv e=energy change, h=planck's constant, v=frequency

PV=nRT labeled

P= pressure (atm), V= volume (L), T=temp (K), R= gas constant .0821 (L•atm/mol•K)

ideal gas law with moles

PV=nRT

[Ar]4s^23d^6 lose 2 electrons

[Ar]3d^6

shorthand electron configuration example

[Xe] 6s2 4f14 5d10

second ionization energy

after first ionization energy electrons has been remove so atom becomes + charged ion so energy require to remove next electron

coulomb's law

amount of energy electron has depends on distance from nucleus

ionization energy

amount of energy needed to remove electron

Photoelectron Spectroscopy (PES)

amount of ionization energy 4 all electrons ejected from nucleus

move to the right periodic table

atomic radius deceases, ionization energy increases, electronegativity increases

when moving from left to right across period what happens to atomic radius?

atomic radius decreases because protons are added to nucleus so valence electrons are more strongly attracted resulting in decrease in atomic radius. if electrons added in same shell same dis from nucleus there is not much shielding effect bc not in Dif levels

when moving down a group what happens to atomic radius?

atomic radius increases because moving down a group shells of electrons are added so each shell shield more distant shells from nucleus and valence electrons get farther away. protons are being added but the shielding effect is too negatively charged and cancels out added positive charge

moving down periodic table

atomic radius increases, ionization energy decreases and electronegativity decreases

ion

atoms which gain or lose electron

molar mass

avg mass 4 1 mole

what happens to binding energy in PES graph

binding energy (ionization energy) decreases from left to right

incoming radiation energy

binding energy + kinetic energy

charge of elements in CuBr2

bromide: +1 (2) = +2 copper: -2

frequency wavelength and spd of light

c=wavelength•frequency c=m/s, wavelength= m, frequency 1/s or Hz

what type of ion are transition metals

cation

electron configuration

complete description of energy level and subshell

dalton ideas

compounds always contain same ratio of elements and never atoms are created or destroyed in chem ratio

molarity

concentration of solution

third subshell

d holds 10 electrons

what happens to metallic characteristics of elements as go right on pt

decrease

when moving down a group what happens to electronegatively?

decrease because more shielding

when moving down a group. what happens to ionization energy?

decreases because shells of electrons added so more shielding which reduces pull of nucleus making it easier to remove electron with less energy

subshells

describe shape of space can b found

relative height of peaks

determine number of electrons in subshell

what do PES peaks represent

different energy level. # of peaks shows us not all electrons at n=2+ are located same distance from nucleus.

atomic radius

distance from nucleus to valence electrons

why anions are larger than atoms?

electrons are being added to atoms so electron-electron repulsion increases causing valence electrons to move farther apart which increases the atomic radius

why are cation smaller than atoms?

electrons are being removing so outer shell is lost making cation a smaller atom. also electrons are removing and electron-electron repulsion is reduced allowing all electrons to move closer to nucleus

quantized

electrons can exist only at specific energy levels

give off energy from electromagnetic radiation

electrons drop from higher to lower energy levels

absorb energy from electromagnetic radiation

electrons jump 2 higher energy levels.

metalloids

elements that borderline between metals and nonmetals

periods represent what?

energy level

fourth subshell

f holds 14 electrons

electrons do not have specific orbits. what do they do?

function in region of space

distance from nucleus and amount of kinetic energy electron has

further away from nucleus require less energy to remove therefore it will move faster

moles

g/Mm

when close to full energy level

gain electron to achieve stability

Coulomb's law qualitatively applied

greater charge of nucleus, the more energy an electron with have. coulomb potential energy for 1s electrons is lower (more negative) than 3s electrons. amount of energy required to remove 1s electrons is greater than amount need to remove 3s bc farther from nucleus so less attration

vertical

groups

s block elements

groups 1 and 2 + helium

p-block elements

groups 13-18

electronegatively trends exceptions

helium, neon, argon don't form bonds but larger noble gases do and follow general trends

what can we examine with speed of ejected electron

how far away they were from nucleus

electronegativity

how strongly nucleus of atom attracts electrons of other atoms in a bond

what happens to electrons potential energy as distance increases from nucleus

increase bc less force from nucleus so more PE to separate from nucleus or bind

why second ionization energy is greater than first ionization energy?

increases because electron removed so electron-electron repulsion decreases and valence electrons move closer to nucleus this increases attractive force between electrons therefore increasing needed ionization energy to remove next electron

when moving from left to right across period what happens to electronegativity?

increases because increase in nuclear charge

when moving from left to right across period what happens to ionization energy?

increases because protons are added to nucleus which increases positive charge. because of this negatively charged valence electrons are more sternly attracted to nucleus which increases energy required to remove them.

f block elements

inner transition metals

moles of atoms for binding energy

kJ/mol or MJ/mol

closer an energy level is to the atom menas

less energy electrons on that level bc smaller ring

molarity equation

moles of solute/L of solution

STP moles, volume equation

moles= liters/22.4(L/mol)

faster an ejected is going...

more KE it has

anion

more electrons than protons

cation

more protons than electrons

how are electrons found around nucleus

moving around a certain (area) sub shell and energy level (distance) away from nucleus

how to calculate percent composition

multiple # of atoms by atomic mass. then find total atomic mass for compound. then divide each element by the total molar mass to find % comp.

all energy of incoming radiation

must be conserved and if doesn't go into break electron free then will be converted into KE

molecular formular

needs molar mass. find molar mass of empirical formula then divide that mass by molar mass given. the answer needs to be multiplied to empirical compound then gives molecular formula

if gain electron

negative ion

atomic number

number of protons

when is most stable configuration from energy standpoint

outermost energy level has 8 electrons (2 in the s and 6 in the p subshell)

valence electrons

outermost s and p subshells

second sub shell

p holds 6

horizontal

periods

lose electron

positive ion

At STP

pressure 1, temp 273 K. can convert directly btwn vol and # of mol bc at STP, 1 mol of gas occupies 22.4 L

binding energy

removal energy of electron and always positive value

shorthand electron configuration

replacing part of configuration w last noble gas that's filled.

first ionization energy

required energy to remove electron

first subshell

s hold 2 electrons

empirical formula

simplest ratio of compound

how to calculate charge of elements in compound

start with metal charge then find gas then multiple by each element by charge to number of element in compound so balance to zero

how to find empirical formula

take grams of each element then divide by element's atomic mass. the one with the smallest moles divide all elements by that amount then gives empirical ratio for compound

molecular formula

the actual formula of a compound

what two factor affect electronegativity

the smaller atom is the more effectively nuclear charge is felt past valence electrons (bc less shielding) and higher electronegatively will be. secondly the closer an element is to having full energy level the more likely ir is to attract necessary electrons

d block elements

transition metals

Pauli Exclusion Principle

two electrons in same orbital cannot have same spin (one clockwise that other counter)

dalton ideas example

water (h2o) always have 2 hydrogen atoms for every 1 oxygen atom

aufbau principle

when building electron configuration electrons re placed in sub shells by increasing energy

hund's rule

when electrons added to subshell always will occupy empty orbital first before pairing up when no empty space

rules for transition metals forming cations

when losing electrons will lose higher-level s electrons before losing any lower level d electrons

as electrons are removed, ionization energy increases gradually until shell is empty, then makes a big jump. why is there a big jump?

when valence shell is empty next electron comes from much closer shell to nucleus making ionization energy for electron much larger

PES graph

y-axis describe relative # of electrons from given energy level. x-axis shows binding energy.