Elements of Life - Atomic Structure Flashcards
What is relative mass measured in comparison to?
The relative mass of a proton or neutron is measured in comparison to (1/12 x carbon12)
What is the relative mass of an electron?
1/1840
What is the general formula for the relative mass?
(mass of isotope x % abundance) + (repeat for all isotopes) divided by 100
What is the formula for relative abundance?
peak height / total peak height x100
After which element does nuclear fusion usually stop and why?
Iron (Fe) too big
Complete the nuclear equation: Hydrogen 1 + Hydrogen 1 ->
Helium 2
Complete the nuclear equation: Helium 2 + a neutron ->
helium 3
under which conditions can nuclear fusion occur?
very high temperatures and pressure due to the electrostatic repulsion of the positive nuclei
What physical state must elements be in for mass spectroscopy?
gas
What is mass spectroscopy used for?
Calculating the masses of different isotopes of the same element
What equation links speed of light, wavelength and frequency?
Speed of light = wavelength x frequency C = λν
What equation links energy, frequency and planck’s constant?
Energy = frequency x planck’s constant E = hν
What is the quantisation of energy?
the theory that subatomic particles have no ‘in between’ speeds -> they go from one to the other instantaneously energy exists in specific packets called quanta
Describe what an absorption spectra looks like
Coloured background with black lines
Draw an example of an absorption spectra graph
Draw an example of an absorption spectra graph
Describe what an absorption spectra looks like
Coloured background with black lines
Describe what an emmision spectra looks like
A black background with coloured lines
Describe how an atomic emmission spectrum is produced
Explain why atomic emission spectrums are unique to particular elements
Excite the atoms to a higher energy level with energy (eg heat)
They then fall from a higher to lower energy level
Energy is quantised and coloured lines are produced as a result of E=hν
Energy levels are unique to the atom and therefore the ν emitted is unique to the atom
How many electrons can S, D and P orbitals hold?
S -> 2
P -> 6
D -> 10
After which element can the outer energy level hold more than 8 electrons?
Beyond Calcium, energy levels can take up to 18 electrons
Define isoelectronic
When two different elements have the same electron configuration
eg K+ = Ar
What is the wave theory of light?
As light is a form of EM radiation, it behaves like a wave
The speed of light is always constant despite wavelength and frequency changing
What is the particle theory of light?
Light exists in packets of energy called photons
How are the wave and particle theories of light linked?
energy of a photon = planck’s constant x frequency
Describe Bohr’s theory about electrons
- > electrons only exist in specific energy levels
- > a photon of light is emitted when an electron changes energy levels
- > the energy of the photon is equal to the energy difference between the 2 energy levels
- > E = hν
Describe how absorption spectras work
White light is passed through a cool sample of a gaseous element
The black lines on the spectrum represent the light absorbed by the atoms
Explain how the atomic emission spectra shows that elements exist in energy levels
Each energy level has a specific frequency due to E = hv
The energy drops between each energy levels produce specific lines
state the major trend in the first ionisation enthalpies across a period
explain in terms of electron energy levels, how this occurs
(from left to right) the ionisation enthalpie increases throughout the period
all electrons are in the same energy level, but as you go across they have more protons and therefore more electrostatic attraction so more energy is required to break them
What is the EM spectrum?
(highest to lowest wavelength)
Radio, Infrared, Visible Light, Ultraviolet, X-Ray, Gamma
