Inorganic Chemistry Flashcards
what is the frequency of a wave?
the number of waves which pass a point in one second
what is the equation for the speed of a wave?
c= f x (upside down) y
what is the speed of light in a vacuum?
3.00 x 10^8ms-1
higher energy means…
higher frequency and so shorter wavelengths
what are the different types of waves in order of frequency from lowest to highest?
low - radiowaves, microwaves, infared rays, visible light, ultraviolet light, x-rays, gamma rays - high
what is the equation for the energy of 1 mole of photons?
E = Lch/wavelength
what is a photon?
a small particle that form a stream (electromagnetic radiation).
what is Avogadro’s constant?
the number of atoms or molecules in 1 mole of a substance i.e. 6.02x10^23
what is Planck’s constant?
the energy in 1 photon of electromagnetic radiation to the frequency of that radiation i.e. 6.63x10^-34 Js
what is monochromatic radiation?
radiation composed of only one wavelength
what is continuous radiation?
radiation that spans a whole array of different wavelengths
what is the region of the visible light spectrum?
400nm- 700nm roughly
how is a line spectrum created?
when electrons gain energy and jump to a higher energy level and then fall back down. when the electrons fall back down energy is released as electromagnetic radiation. if the frequency of this electromagnetic radiation is within the visible spectrum then colored lines will be observed.
what does each line in the atomic emission spectrum correspond to?
the energy given out when an excited electron moves from a higher energy level to a lower energy level.
the energies between energy levels are…?
fixed. therefore the energy levels themselves are fixed and so the electrons have fixed energies.
what is the Balmer series?
the part of a complete spectrum that produces visible light.
what is the Lyman series?
the part of a complete spectrum that produces ultraviolet light
what is the Paschen series?
the part of a complete spectrum that produces infared radiation
how do electrons behave in quantum mechanics?
they behave as standing waves of fixed energy within an atom
what is an orbital?
a 3 dimensional region in space.
how many electrons can an orbital hold?
a maximum of 2
what is the principle quantum number?
‘n’ the number which indicates which shell the electron will be in (corresponding to energy levels).
what is the second quantum number?
the angular momentum quantum number ‘l’. this governs the shape of the orbital.
what is the third quantum number?
the magnetic quantum number m(lower)l relates to the multiplicity and orientation of the orbital. this ranges from n to minus n where n relates to the number of energy levels.
what is the fourth quantum number?
the spin quantum number m(lower)s - describes which way an electron is spinning (clockwise or anticlockwise) and is shown as 1/2 or -1/2
what is the formula for calculating the number of electrons at each energy level?
2n^2 where n refers to the number of energy levels.
what are p-orbitals?
dumbell shaped orbitals that have 3 degenerate orbitals at each appropriate energy level. (px,py,pz) where l = 1
what are s-orbitals?
spherical orbitals. there can only be 1 s orbital at each energy level. where l = 0
what are d-orbitals?
double dumbell shaped orbitals that have 5 degenerate orbitals (oriented differently) at each (appropriate) energy level. wher l = 2
what are degenerate orbitals?
orbitals of equal energy
what is the Pauli Exclusion principle?
no 2 electrons can have the same set of four quantum numbers. this is because two electrons in a shell will have opposite spins therefore they cant have the same quantum numbers.
what is the Aufbau principle?
orbitals are filled in order of increasing energy
what is Hund’s rule?
when degenerate orbitals are available, electrons occupy separate orbitals individually, with parallel spins, until all of the orbitals have one electron before painring up.
what is the order of increasing energy in orbitals? (i.e. 1s,2s…)
1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d,5p, 6s, 4f, 5d, 6p, 5f, 6d
what is the s block?
groups 1 and 2 where every element has an electon configuration that ends in an s orbital
what is the p block?
groups 3-0 where every element has an electron configuration that ends in a p orbital
what is the d block?
the transition metals where every element has an electron configuration that ends in a d orbital
what is the f block?
the lanthanide and actanide series’ where every element has an electron configuration ending in an f orbital
what are the 2 methods of expressing electron configurations?
orbital box notation and spectroscopic notation
Why do degenerate orbitals have equal energy?
Because they have the same principle quantum number ‘n’ and the same angular momentum
Is the energy of a photon associated to the frequency of the radiation
Yes
What happens when a wavelength increases ?
Frequency decreases
Are 1/2 filled degenerate orbitals stable ?
Yes. If every degenerate orbitals is 1/2 filled then that orbital is more stable than one with an unequal amount of electrons in the degenerate orbitals.
What requires more energy - removing an electron from a partially full orbital or removing an electron from a stable / orbital ?
Removing an electron for a stable or filled orbital
How many lines are in the visible region of the hydrogen emission spectrum ?
5
What is the alpha line in the hydrogen emission spectrum ?
656nm - where there is a transition between n=2 and n=3
What is ionic character ?
The difference in electronegativity values where the highest ionic character is found in the molecule with the highest difference in electronegativities.
What is covalent character ?
Electronegativity differences where the molecule with the highest covalent character has the lowest difference in electonegativies
What is a convergence limit ?
Where the lines on a spectrum converge representing the first ionisation energy (?)
