3.1.1 Flashcards
atomic structure
what is the relative mass of an electron?
1/1840
what force holds together protons and neutrons/
hint- where are they located?
nuclear force
what’s the definition for relative atomic mass and relative molecular mass?
the mass of a single Atom (Ar)/ molecule (Mr) relative to 1/12 of a carbon atom
what’s the equation for the relative atomic mas of isotopes?
Ar=(mass of isotope 1 * %abundance) + (mass of isotope2 * %abundance)
what is the maximum number of electrons per orbital?
2
what is the Aufbau principle?
electrons always fill up the lowest energy levels first
which orbital has six electrons?
P orbital
what is Hund’s rule?
electrons would rather have their own orbitals before pairing up.
what is the electron configuration for an element with 9 electrons
1s2 2s2 2p5
how many total electrons in the D orbital?
10
many electrons in the S orbital?
2
in time of flight calculations, what is he equation for Kinetic energy?
Ek = 1/2 * m * v^2
what three factors effect ionisation energy?
radius
electron shielding
nuclear charge
does ionisation energy increase or decrease across a period?
increase
in time of flight calculations, what is the equation for velocity?
v= d/t
what is the value of Avogadro’s constant (1 mole)
6.022* 10^23
does ionisation energy increase or decrease down group?
decrease
what is he definition of ionisation energy?
the amount of energy required for one mole of an element/compound to lose 1 mole of electrons.
describe electron impact ionisation?
an electrons are fired at the sample, this nocks off one of the samples electrons from orbit creating a positive ion -because one electron is lost.
in time of flight mass spectroscopy, what is used to accelerate the ions?
an electric field
what is the detector in time of flight mass spectroscopy?
a negatively charged plate
how does electrospray ionisation occur?
the sample is dissolved in solvent and then fired through a positively charged hypodermic needle, the solvent evaporates and the sample gains a proton creating a positive ion.
after acceleration, the ions all have the same what?
kinetic energy
what does time of flight mass spectroscopy find?
the mass and percentage abundance of ions
what are the four stages of time of flight mass spectroscopy?
ionisation
acceleration
ion drift
detection
what are the two types of ionisation in time of flight mass spectroscopy
electrospray ionisation
electron impact ionisation
is nuclear force strong or weak
strong
what technique is used to find the relative mass of elements and compounds?
time of flight mass spectroscopy
what force holds electrons to protons?
electrostatic force
