Midterm 1 Flashcards
What can matter be separated into
Pure substances and mixtures
What can pure substances be separated into
Elements and compounds
What can mixtures be separated into
Homogeneous and heterogeneous
What is the difference between elements and compounds
Elements are made of one type of atom and compounds are made of more than one type of atom
What are the five hypothesis’ of dalton’s atomic theory
1) matter is composed of extremely small particles called atoms
2) an element consists of only one type of atom
3) atoms of one element differ in properties from atoms of all other elements
4) a compound consists of atoms of two or more elements combined in a small, whole number ratio
5) atoms are neither created nor destroyed during a chemical change
What three laws did dalton’s atomic model account for
1)Law or conservation of matter
2) law of constant composition
3) law of multiple proportions (two elements can react to form more than one compound), carbon oxygen can form one thing or another thing
What did JJ Thompson show and through what experiment
The existence of electrons through the cathode ray tube
What were JJ Thompson’s 3 conclusions on electrons
1) negatively charged particles
2) less massive than atoms
3) particles were indistinguishable regardless of the source material (cathode ray)
What were the two things Millikan calculated in the oil drop experiment
1) charge of an electron
2) used Thomson’s charge to mass ratio to calculate the mass of an electron
What does Thomson’s plum pudding (raisin bun) model show
Electrons are dispersed in a cloud of positively charged matter
What is the modern representation of the atomic structure called
And what did it show
The nuclear atom
Showed that a positively charged mass is present in the atom and there was a lot of space
Atomic symbols: What does the left superscript show
Mass number
What is mass number
Number of protons + neutrons
Atomic symbols: what does a left subscript show
Atomic number
What is atomic number
=protons = electrons in a neutral atom
How to determine the number of neutrons in an atom
Mass #- atomic #
(Left superscript-left subscript)
What are isotopes
Atoms of the SAME element with the SAME # of protons but DIFF # of neutrons
What is atomic mass and where is it on the periodic table
An average # based on the amount of each isotope in nature
Located in the bottom of each element
Where is atomic number on the periodic table
Top left
What are ions
An atom or group of atoms that carry a net positive or negative charge
What is a cation and what is it’s charge
Formed when an atom LOSES electrons (+ charge)
What is an anion and what is it’s charged
Firmed when an atom GAINS electrons (- charged)
Why do ions form and when
Some atoms have a tendency to lose electrons and others have the tendency to gain electrons
Happens during chemical reactions
What is a column of elements called
And what do they have in common
Group
Have similar properties and reactivities
What is a row of elements called
Period
How are groups labeled
From left to right
How to figure out charge and when elements could have two charges
___\
Ionic compounds 1st group: , What are they formed from and what are they a combination of
And what element does what
Formed from monoatomic
Combination of metal and non metal because opposite charges attract
Metal loses electrons to form cation
Non metal gains electrons to form anion
Steps for naming ionic compounds
1) name cation
2) add “ide to name of the anion
3) specify charge of metals that form MORE than one ion in Roman numerals
What are monoatomic ions
____
What are polyatomic ions
____
Ionic compounds 2nd group: what are they combined of and what do they exist as
2 or more atoms that have been joined by covalent bonds
Exist as a charged unit
What are covalent bonds
____
How to name ionic compounds formed from polyatomic ions
____
Polyatomic ion: ammonium
(cation or anion)
NH4+
Cation
Polyatomic ion: hydronium
(cation or anion)
H3O+
Cation
Polyatomic ion: acetate
(cation or anion)
CH3COO-
or
C2H3O2-
Anion
Polyatomic ion: cyanide
(cation or anion)
CN-
Anion
Polyatomic ion: hydroxide
(cation or anion)
OH-
Cation
Polyatomic ion: hypochlorite
(cation or anion)
ClO-
Anion
Polyatomic ion: chlorite
(cation or anion)
ClO2-
Anion
Polyatomic ion: chlorate
(cation or anion)
ClO3-
Anion
Polyatomic ion: perchlorate
(cation or anion)
ClO4-
Anion
Polyatomic ion: nitrite
(cation or anion)
NO2-
Anion
Polyatomic ion: nitrate
(cation or anion)
NO3-
Anion
Polyatomic ion: permanganate
(cation or anion)
MnO4-
Anion
Polyatomic ion: carbonate
(cation or anion)
CO3(2)-
Anion
Polyatomic ion: hydrogen carbonate/ bicarbonate
(cation or anion)
HCO3-
Anion
Polyatomic ion: chromate
(cation or anion)
CrO4(2)-
Anion
Polyatomic ion: dichromate
(cation or anion)
Cr2O7(2)-
Dichromate
Anion
Polyatomic ion: peroxide
(cation or anion)
O2(2)-
Anion
Polyatomic ion: phosphate
(cation or anion)
PO4(3)-
Anion
Polyatomic ion: hydrogen phosphate
(cation or anion)
HPO4(2)-
Anion
Polyatomic ion: dihydrogen phosphate
(cation or anion)
H2PO4-
Anion
Polyatomic ion: sulfite
(cation or anion)
SO3(2)-
Anion
Polyatomic ion: sulfate
(cation or anion)
SO4(2)-
Anion
Polyatomic ion: hydrogen sulfate/ bisulfate
(cation or anion)
HSO4(2)-
Anion
What is the first type of covalent compounds and what are they a combination of
Binary compounds
Combination of non metal and non metal
How to name binary compounds
1) add “ide” to the end of second element
2) add numerical prefixes to both elements to indicate the subscript of each element
-don’t use mono for the first
What are the covalent compound prefixes in order
Mono
Di
Tri
Tetra
Penta
Hexa
Hepta
Octa
Nona
Deca
What is the second type of covalent compounds and what do they contain at least one of
(And why)
Acids
Contain at least one hydrogen atom
Because acids produce hydronium ions (H3O+) when dissolved in water
What are binary acids made of and how do you name
H bonded to another non metal or polyatomic ion
Naming
1) hydro_____ic acid
What are oxyacids made of and why
Contain H, O, and another non metal
Combination of oxygen and other non metal forms an oxoanion
How to name oxyacids
1) identify group
XO- : hypo_____ite
___
_
What are the 3 parameters that characterize a wave
Wavelength
Frequency
Speed
What is wavelength
Distance between two consecutive crests or troughs
What is frequency, and what variable is it
Number of complete cycles that pass a given point per second
v
What is speed (in waves), and what variable is it
Distance a wave propagates per unit time
s
What formula relates the 3 wave parameters and what is each measured in
s=v(wavelength)
s=m/s
v=Hz or s^-1
wavelength=nm
What is a wave
A vibration by which energy is transmitted
As frequency increases, _____ decreases
Wavelength
As wavelength increases, ______ decreases
Frequency
What were Max Plancks two conclusions
1) energy can be emitted only in discrete energy packets rather than in a continuous wave
2) energy is quantized and it constitutes of small packets called quanta
What is a quantum
The smallest amount of energy that can be absorbed or emitted in the form of electromagnetic radiation
What formula describes the energy of a quantum
E=hv
The change in an atoms energy occurs when the atom ____/_____ one or more quanta
And what formula describes this
Emits/absorbs
triangle E=nhv
Where n=1,2,3…
What happened in the photoelectric effect
When a metal surface is exposed to light, electrons are ejected
Three observations that are characteristics of the photoelectric effect
1) presence of a threshold frequency (V not)
2) intensity of light shine onto the metal surface
3) Frequency and Ek of the ejected electrons
Photoelectric effect: no electrons leave the ____ of the metal ____ the threshold frequency, each metal has its own ______ _____
Surface
Below
Threshold frequency
Photoelectric effect: an electron can only break free when it _____ enough energy to ____ its attraction to the ______
Absorbs
Breaks
Atom
Photoelectric effect: increasing the ______ of the light shone on the metal surface above the _____ ____ DOESNT _____ the # of electrons ejected
Frequency
Threshold frequency
Increase
Photoelectric effect: increasing the ____ of the light with frequency above the _____ ___ DOES ____ the # of electrons ejected
(And why)
Intensity
Threshold frequency
Increase
(Higher intensity light has more photons and each photon is used to free an electron)
Photoelectric effect: increasing frequency of the incident light=____ Ek of the elected electrons
(And what type)
Increasing
(Linear)
Photoelectric effect:
Formula that relates frequency and kinetic energy of the ejected electrons
(And what do all the v’s represent)
Ek=hv-hv(not) = (1/2)mv^2
1st: freq of incident light
2nd: threshold freq
3rd: velocity of electrons after ejected
Ek=E-_____
E(not)=hv(not)=____
E(not)
Min amount of energy required to extract an electron
Photoelectric effect: when question says “1 mole of photons” what do you have to do
Multiply final answer by avagadro’s number
Atomic specta: elements give________ line spectra
Discontinuous
What are the four quantum numbers and what variable do they go with
1) principal quantum #, n
2)angular momentum, l
3) magnetic quantum #, ml
4) electron spin quantum #, ms
What is “n” and how do you find it
Defined the size and energy of the orbital
Find through periodic table
As “n” gets bigger it means a bigger ____, which is also at higher ____, because it’s farther from the nucleus
Orbital
Energy
What is “l” and how do you find it
Describes the shape (type) of orbital
Allowed values are from 0 to (n-1)
What are the corresponding orbitals to the “l” value
l=0 s orbital
l=1 p orbital
l=2 d orbital
What is “ml” and how do you find it
Refers to the 3D orientation of the orbital in the space surrounding the nucleus
ml= -l to +l
What are the corresponding orbitals to the “ml” value and how many spaces do these orbitals have
ml=0 s orbital (only 1)
ml= -1,0,1 p orbital (3)
ml= -2,-1,0,1,2. d-orbital (5)
What does the d orbital having 5 spaces mean
Set of 5 orbitals in 5 different orientations
What is “ms” and how do you find it
Describes the orientation of the electron occupying the orbital
-1/2 down spin
1/2 up spin
Electrons are orbiting the nucleus and also ____
a -1/2 parked with 1/2 ____ the atoms ability to produce its own _____ field
Spinning
Reduces
Magnetic
Two electrons in an orbital CANNOT be characterized by the ____ set of quantum numbers
Every number can be the same EXPECT ___
Same
ms
What are orbitals also called
Sub shells
What is the ml value of the s orbital
What is the ml value of the p orbital
0
-1,0,1
What is the l value of the s probital
What is the l value of the p orbital
What is the l value of the d orbital
0
1
2
What is orbital notation
What are the 4 #’s for 3S
n(l) subscript (ml)
n=3
l= 0
ml=0
ms= -1/2 or 1/2
Why doesn’t the 2d orbital exist
n=2
So l=0
l=1
There can only be s and p orbitals (cuz of l values)
Pauli’s exclusion principle: a given orbital CANNOT contain two electrons with the same ___ because two electrons cannot have the same set of _____ _____
Spin
Quantum numbers
What is a node
And what can they also be called
Regions where electrons can’t go
Spectral nodes or nodal spheres
Formula for finding # of nodes in an orbital
How many nodes does 1S have? 3S?
of nodes =n-1
1S= no nodes
3S= 2 nodes
Probability density is the highest _____ to the nucleus
(And why)
closest
(Small area/ given amount of electrons) = large density
So higher chance of finding an electron in a smaller area
Stoich steps
1) write a balanced equation
2) calculate moles of 1st reactant
-con
Maybe add pic
At the nucleus the radial probability distribution is ___
0
In a radial probability distribution graph, everytime the line touches the x axis its a ____
Node
What do Pz, Px, and Py orbital looks like
Pz= two flower petals OVER on z axis
Px= two flower petals OVER x axis
Py= two flower petals OVER y axis
How do you indicate nodes in drawings
+ and - signs
How many d orbitals are there, what are they, what planes are they orientated on
5
dyz = on y and x axis
dxz = on x and x axis
dxy = on x and y axis
dx^2-y^2 = oriented DIRECTLY on x and y axis
dz^2 = oriented DIRECTLY on z axis with ring in between
How to draw d orbitals in 2 d
Switch labels of the two axis
Where to draw flower petals for d orbitals
(And two exceptions)
BETWEEN the axis lines
dx^2-y^2
And
dz^2
Are oriented DIRECTLY on axis lines
Example of a one electron atom
Hydrogen
In a one electron atom, orbitals with the same ___ have the ____ energy
(What does this look like)
n
Same
3S, 3p, 3D orbital are all in line in the same level
Degenerate
Have the same energy
In a many electron atom orbitals with the same ___ have ___ energy
n
Different
Many electron atoms: the ___ orbital is ____ penetrating than the p and d orbitals
s
more
Many electron atom: does the 2p or 2s have more energy
2p
Orbital penetration means that the orbital has ___ electron ____ closer to the nucleus
Higher
Density
In a radial probability graph does the 2p or 2s reach its max first and why
2p max happens first
The electrons in the 2p spend more time closer to the nucleus because it has a smaller radius
What is shielding
Electrons on an energy level closer to the nucleus shield energy levels further away from the nuclear attractive force
More shielding= ____ penetrating=____ energy
More
Less
Less shielding=___ penetrating= _____ energy
Less
Higher
What is the order from most shielding to least shielding
s,p,d,f
As the number of ____ increases and ofc number of electrons increases, the energy of the orbital goes ____
Protons are able to ___ electrons closer, so electrons get ___ to the nucleus and are ____ in energy
Protons
Down
Pull
Closer
Lower
Greater nucleus charge ____ orbital energy
Lowers
Electron electron repulsion _____ orbital energy because repulsion _____ the system
Increases
Stabilizes
Electrons in outer orbitals are ___ shielded from the full nuclear charge so they have ____ energy
Shielded
Higher
Orbitals with good penetration have ___ energy
Lower
What is good penetration
Have electron density closer to the nucleus
Formula for Zeff
(And what does inner shell mean)
of protons-inner shell electrons
Inner shell= all other shells except last occupied shell
Force of attraction the outer electron will feel is determined by ______
Zeff
Larger ___= outmost electrons are feeling ____ pull= makes atom ___
More
Smaller
What does the superscript when writing electron configurations show
How many electrons are on that level
What is paramagnetic
More unpaired electrons= _____ attraction to magnetic field
There’s at least one unpaired electron
Higher
What is diamagnetic
And they are repelled by a ____ ___
No unpaired electrons
Magnetic field
The Aufbau principle: when an atom or ion is in its ____ state, electrons fill the orbitals of the ____ available energy before occupying higher energy levels
Ground
Lowest
Order for filling orbitals with electrons
1S, 2S, 2P, 3S, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6S, 4f, 5d, 6p, 5f, 6d, 5g, 6f, 6g, 6h
How to figure out the number of VALENCE electrons in condensed electron configuration
All the subscripts added up
How to figure out the number of INNER SHELL electrons in condensed electron configuration
All the electrons in the square brackets
When ionizing you take the electrons from the ___ numbered shell
What she’ll wojld you take electrons from 3S or 4s
HIGHEST
4s
Pg 40-43
___
Elements are arranged in the periodic table in increasing ______ ____
Atomic number
What are the three periodic table trends
-atomic size and ionic size
-ionization energy
-electron affinity
Atomic size: in a group atomic size/atomic radius increases ____ a group
And why
Down
The # of electrons increases and the occupy a new shell, more shielding, size increases
Which way does a period go for trends
Left to right
Atomic size: in a period atomic size/atomic radius ____ across a period
And why
Decreases
Zeff increases and stronger nuclear attraction pulls electrons closer to the atom
Metals lose valence ____ to form ____
Nonmetals gain valence ___ to form ___
Electrons
Cations
Electrons
Anions
Oxidation numbers!!
___
How to predict the “magnetic behaviour” of ions in a compound!!!
——
Trends in ionic radii: ionic radius ____ down a group but ______ across a period
Increases
Decreases
Trends in ionic radii: higher proton to electron ratio= ____ size
Smaller
What is a high ratio!!!
__
Is ionization endothermic or exothermic and why
Endothermic because it requires energy
Does first ionization require more energy or 4th
And why
4th
since those electrons are closer to the nucleus
Trends in ionization energy: ionization energy of elements _____ down a group
And why
of core electrons increases, so more shielding, so easier to remove outside electron
Decreases
Trends in ionization energy: ionization energy of elements ____ across a period
And why
Increases
Zeff increases across a period
Trends in ionization energy: Na has one valence electrons and Mg has 2, which has the higher 2nd ionization energy
And why
Na
Because it takes more energy to remove a core electron since with Mg there’s another valences electron to remove
Trends in ionization energy: what is the first discontinuity
Why
How does this discontinuity extend
B has LOWER ionization energy than Be
B has three orbital levels while Be, only has two, so there’s more shielding is higher in B, easier to take an electron out
Extends vertically down those elements
Trends in ionization energy: what is the second discontinuity
Why
How does this discontinuity extend
O has LOWER ionization energy than N
In the out shell of N all the electrons are unpaired, makes it the most stable, so more energy needed to remove electron, electron electron repulsion forces in outer shell of O makes electron easier to remove
Discontinuity extends vertically down
Trends in electron affinity: it is the ___ change that occurs when an atom or ion in its ____ state ____ an electron
And what does it depend on
Energy
Gaseous
Gains
Depends on atomic size
Is electron affinity endothermic or exothermic
and why
Exothermic
Cuz the nucleus must attract the electron strongly enough
Trends in electron affinity: across a period EA ___
And why
Increases
Because atomic size decreases
Trends in electron affinity: down a group EA ____
And why
Decreases
Because atomic size increases
Is EA value positive or negative
Negative
Larger EA (not including negative sign) = ____ for atom to accept the electron
Easier
Oh 51-53!!!
___
What are group 1 elements called
And what is their fundamental characteristic, so they are ____
Alkali metals
The ease with which they lose their valence electron, so very reactive
Oxidation state of oxygen
-2
Oxidation state of hydrogen
+1
Oxidation state of group 2 metals (and where are they located)
+2
Second from the left
Which is the oxidizing agent
The one being reduced
What is the reducing agent
The one being oxidized
