MCAT General Chemistry Review: Chapter 1 Flashcards
Orbitals
Electrons move rapidly and are localized within regions of space around the nucleus called orbitals
Heisenberg Uncertainty Principle
It is impossible to simultaneously determine, with perfect accuracy, the angular momentum and position of an electron
Four quantum numbers
n, l, m_l, m_s
-=subscript
Avogadro’s number
6.02 x 10^23
The atomic weight of carbon is 12.0 amu. The average carbon atom had a mass of 12.0 amu and 6.02 x 10^23 carbon atoms have a combined mass of 12.0 grams.
Quanta
Energy emitted as electromagnetic radiation from matter comes in discrete bundles.
Discrete bundles of energy in the form of electromagnetic radiation
Planck relation (energy of a quantum)
E=hf
Plancks constant
6.626 x 10^-34 J•s
f
Frequency
Kinetic energy formula
K=1/2mv^2
K=kinetic energy
M=mass
V=Velocity (m/s)
Speed of light formula
V=f¥ (lambda)
Speed of light (c)
3x10^8 m/s
Angular momentum formula
L=nh/2pi
n=principal quantum number
h=plancks constant
Energy of the electron
E=-RH/n2
E is directly proportional to n (hence the negative sign)
Rydberg unit of energy
2.18x10^-18 J/electron
As electron go from a lower energy level to a higher energy level, they ____
Absorb light, higher potential, excited, distant from nucleus
Electromagnetic energy of photons formula
E=hc/wavelength (lambda)
Energy transitions do not form a continuum but rather are quantized to certain frequencies. A _____________ (2) is where each line on the emission spectrum corresponds to a specific electron transition. Because each element can have its electrons excited to a different set of distinct energy levels each possess a unique ____________(3) which can be used as a fingerprint for the electron.
Line spectrum; atomic emission spectrum
E=hf=hc/wavelength(lambda)
Energy is _______proportional to wavelength
Inversely
E vs -E
Positive E= emission
Negative E= absorption
E=hc/wavelength = _______
-RH[1/ni^2 - 1/nf^2]
Also—-
-E= -RH[1/ni^2 - 1/nf^2] AND E= -RH[1/ni^2 - 1/nf^2]
(Emission vs absorption)
Delta E is the same for absorption and emission between any two energy levels according to the law of__________
Conservation of energy
Heisenberg uncertainty principle
It is impossible to simultaneously determine, with perfect accuracy, the angular momentum and the position of an electron.
Pauli exclusion principle
No two electrons in a given atom can possess the same set of four quantum numbers (n,l,ml,ms)
Spectroscopic notation
Shorthand representation of the principal and azimuthal quantum number (ex:1s,6p,3d, etc.etc.)
Maximum number of electrons within a subshell
4l + 2
Maximum number of electrons within a shell
2n^2
Aufbau Principle
Aka building Principle–electrons fill from lower to higher energy subshells and each subshell will fill completely before electrons begin to enter the next one
The n+l rule
Used to rank subshells by increasing energy. The lower the sum of n+l, the lower the energy of the subshell. If two subshells possess the same n+l value, the subshell with the lower n has a lower energy and will fill with electrons first.
Hunds Rule
Within a given subshell, orbitals are filled such that there are a maximum number of half filled orbitals with parallel spins. (Electrons prefer their own seat on the bus before doubling up with another electron)
Paramagnetic
A magnetic field will cause parallel spins in unpaired electrons and therefore cause an attraction
Diamagnetic
Materials consisting of atoms that have only paired electrons will be slightly repelled by a magnetic field and are said to be diamagnetic
