Exam 1 Flashcards
The law of conservation of matter/the law of conservation of mass–energy
Initial mass and energy=Final mass and energy
The law of conservation of matter is also known as the law of conservation of mass–energy. Initially proposed by Albert Einstein, this law suggests that while the total mass and energy of a system is conserved, mass and energy can interconvert. We’ll discuss energy in much greater detail in Chapter 11: Chemical Kinetics.
White light is a mixture of _____________________
All visible light colors
What is color determined by?
The only wavelength of light that isn’t absorbed (The reflected color is the one we see)
What is frequency? What are the unit and symbols?
The number of waves passing a given point per unit of time?
Hertz, v
Frequency (v) and wavelength (λ) are ___________ proportional
inversely
What is the energy of a wave proportional to?
Amplitude and frequency of a wave
What speed do all electromagnetic waves move at?
Light speed, c, 3x10^8 m/s
What happens when traveling waves encounter an opening in a barrier?
They bend around it, and it looks like the wave is starting from the opening
How do the waves meet when they encounter an opening in a barrier?
Interact with alternating constructive and destructive waves
What does the EM spectrum include?
All wavelengths of EM radiation
What are the types of EM radiation with increasing frequency?
GXUVIMR
Johannes Rydberg
Analyzed the spectrum of Hydrogen, created Rydberg equation
1/λ=Rh(1/nf^2-1/ni^2)
Max Planck
Discovered energy emitted in packets called quanta and proposed that atoms needed to move at a minimum speed to emit energy
Albert Einstein
Expanded on Planck’s work, interpreted Hertz’ PE effect. Proposed the existence of photons, small particles of EM radiation.
Applied Planck’s formulas to photons
Heinrich Hertz
Observed that when a metal absorbs sufficient energy its electrons are ejected from the surface. Known as “photoelectric effect”. Requires a certain frequency
Neils Bohr
Merged Rutherford’s nuclear model of the atom with Planck’s and Einstein’s ideas about quantum theory to create the Bohr model
Louis de Broglie
Said all subatomic matter in motion could be treated as a wave
Heisenberg
Can’t know location and momentum of an e- with absolute certainty
When an element absorbs energy, a unique ________ of light is emitted
absorbs
When emitted light is directed into a prism, a
What is blackbody radiation?
What is the emission of BB radiation called?
Incandescence
What is Planck’s formula?
E=hv=hλ
What is the photoelectric effect?
When the intensity of light is above v=o, # e- increases with intensity and KE of e- increases with frequency
How do you calculate the minimum energy needed to remove an electron?
The threshold frequency-
E0=hv0
Photoelectric effect: When v>v0, the excess energy needed to remove an e- is given as
Kinetic energy
How can you calculate wavelength using energy and planck’s constant?
E=λh
How can you calculate the number of photons in a beam?
E pulse (J)/E photon (j)=# of photons
How do you calculate the energy of a photon?
E=hv=hc/λ
What are the main ideas of the Bohr model?
Electrons can only move in fixed orbits around the nucleus which are described using positive integers
When n=1, this is called the
Bohr radius
What is the closest an electron can be to the nucleus? (Why e- don’t crash into the nucleus)
n=1
What did Bohr propose about each orbit? What was the formula?
It had an assigned energy to it- En=-2.18 x 10^-18J (1/n^2)
What is Coulomb’s law? (not the formula)
The coulombic potential energy is dependent on the charges of the particles and the distance between them
What is the formula for Coulomb’s law?
E= kQ1Q2/d
k=8.99x10^9nxm^2/c^2
Why is Bohr’s equation negative
To reflect difference in charges between e- and p+
When do you use Delta e=-2.18 x 10^-18J (1/nf^2-1/ni^2)
Photoemission questions
Hund’s Rule
Electrons won’t enter an orbital with an electron if there’s one that is empty already
Aufbau Principle
Lower orbitals are filled before higher ones
Pauli-exclusion principle
Electrons will never have the same set of 4 quantum numbers
What is unique about transition metal’s configuration? HOWEVER, if you are being asked about a transition metal, after you find the Aufbau (lowest energy answer), look again.
S electrons move to the D spaces a lot to create symmetry
What is the l value for s?
0
What is the l value for p?
1
What is the l value for d?
2
What is the l value for f?
3
What do all alkali metals have in their subshells? [noble gas]s1 (aka half filled s subshells) and the alkaline earth metals are all [noble gas]s2 (aka filled s subshells) in terms of their valence (outermost shell) configuration
Half filled subshells
What do all alkaline earth metals have in their subshells?
Filled subshells
When do transition metals need to move over one electron?
What groups does the p subshell apply to?
Last 6 groups on the PT
How many degenerate orbitals does the p subshell have? What are they? How many electrons can it hold?
3, (-1, 0, 1), 6
What do all noble gases have in terms of their shells?
Completely filled subshells (Filled s and filled p and f except for helium)
The group that starts with nitrogen contains all of the elements that are [noble gas]s2p3 which are half-filled (aka have one electron in each of the three degenerate orbitals) in terms of their valence configuration. As such, this column of elements is relatively stable.
What groups do the d subshells correspond to?
The middle 10 groups on the PT
What is the ml for d?
-2, -1, 0, 1, 2
How many electrons can the d subshell hold?
10
The group that starts with manganese contains all of the elements that are [noble gas]s2d5 which are half-filled (aka have one electron in each of the five degenerate orbitals) in terms of their valence configuration. As such, this column of elements is relatively stable.
The group that starts with zinc contains all the elements are [noble gas]s2d10 which are filled (aka have two electrons in each of the five degenerate orbitals) in terms of their valence configuration. As such, this column of elements is even more stable.
The experiment that determined that electrons were negatively charged particles was
The Thomson cathode ray experiment
_________ bonds share e-
Covalent
__________ bonds have an attraction between 2 particles
Ionic
Ionic compounds arrange themselves in an array of ________, while molecular compounds only form a few discrete _______
ions, bonds
Who proposed e- in H atoms can only have certain energies?
Bohr
What is the value of L for the orbital shown below?
Provide the quantum numbers and related information for the following orbital, 4f.
What is the principal quantum number, n?
4
Provide the quantum numbers and related information for the following orbital, 4f.
What is the angular momentum quantum number, l?
3
Provide the quantum numbers and related information for the following orbital, 4f.
What is the number of degenerate orbitals based on the magnetic quantum number?
7
What is the formula for ml?
2l+1
What is the formula for finding radial nodes?
n-l-1
How many orbitals are present in the g shell?
9
