Atomic Structure and Isotopes Flashcards
what two parts does the atom consist of
the nucleus and the electrons
what does the nucleus consist of
protons and neutrons
what are protons
positively charged particles
what are neutrons
neutrally charged particles
where are electrons found
in energy levels/orbitals
what is the relative mass of a proton, neutron and electron
proton - 1
neutron -1
electron - 1/1840
what is the relative charge of a proton, neutron and electron
proton +1
neutron 0
electron -1
why is an atom neutral
it has the same number of protons and electrons
what is the atomic number(Z)
number of protons in the nucleus of an atom
what is the mass number (A)
the total number of protons and neutrons in the nucleus of an atom
what is the most useful information to a chemist and why
the number of electrons, because the outer electron structure determines the chemical properties of an element
periodicity
a property is repeated across each period
what are all the 5 shells
1s
2s, 2p
3s, 3p, 3d
4s, 4p, 4d, 4f
5s, 5p, 5d, 5f
what is the order of sub-shells
1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s
how do you find the group of an element using the electron configuration
count the electrons in the outer shell e.g. all the 3’s or 4’s
how many orbitals does an s sub-shell have
1
how many orbitals does a p sub-shell have
3
how many orbitals does a d sub-shell have
5
how many electrons can an s sub shell hold
2
how many electrons can an p sub shell hold
6
how many electrons can an d sub shell hold
10
how many electrons can an f sub shell hold
14
orbital
a region around the nucleus that electrons can occupy. It holds a maximum of 2 electrons with opposite spins
what is the shape of an s orbital
spherical
what is the shape of a p orbital
dumbell shaped
define s/p block element
the highest energy electron in the atom is in an s/p orbital
define d block element
the last electron in the atom goes into a d orbital
what is special about the electron configurations of chromium and copper
a full sub-shell and half-filled sub-shell are stable configurations
what do you do when a transition metal atom becomes a positively charged ion
lose the 4s electron first then the 3d electrons
Isotope
different atoms of the same element with the same number of protons but different numbers of neutrons in their nuclei
why do isotopes of the same element have similar chemical reactivity
they have the same electronic structure/same electronic configuration
why do isotopes of the same element have different physical properties
they have a different mass
which isotope is more reactive, 35-Cl or 37-Cl
neither would be more reactive because they have the same electronic strucutre
in what 2 ways are isotopes similar
same number of protons in their nuclei
the react in the same ways
is atomic radius of 35-Cl larger than the atomic radius of 37-Cl
it is the same as each isotope has the same nuclear charge and same number of electrons
relative atomic mass
the weighted average mass of an atom of an element relative to 1/12th the mass of an atom of carbon-12
why is the relative atomic mass of some element not a whole number
some element have different isotopes so their relative atomic masses are a mean value
relative isotopic mass
the mass of an atom of the isotope relative to 1/12th the mass of an atom of carbon-12
State two features of the current model that are not shown in the Rutherford model.
Current model includes: neutrons and protons
Current model shows electrons in different energy levels/orbitals
State two differences between the ‘plum pudding’ model and the model of atomic structure used today.
(Central) nucleus contains protons and neutrons.
Electrons are now arranged in energy levels/shells/orbitals
In terms of sub-atomic particles, state the difference between the three isotopes of magnesium.
They have different numbers of neutrons
State how, if at all, the chemical properties of these isotopes differ. Give a reason for your answer.
No difference in chemical properties
Because all have the same electronic structure (configuration) OR they have the same number of outer electrons
State 2 features of the current model that are not shown in the Rutherford model (2)
Current model includes neutrons AND protons
Current model shows electrons in different energy levels/orbitals
