1. Atomic structure ( ORBITALS + IONISATION) Flashcards
Define an orbital
a region of space in an atom containing up to two electrons with opposite spins
Give the 4 orbitals in an atom
s p d f
What is the shape of the s orbital compared to the p orbital
s orbital is spherical and p orbital is dumbell shaped
What are the names of the 3 P orbitals
Px, Py and Pz
How many electrons can the p orbital hold
6
Give the maximum number of electrons in each shell
shell 1 - 2
shell 2 - 8
shell 3 - 18
shell 4 - 32
Give the order in which electrons fill subshells
1s–> 2s –> 2p –> 3s –>3p –> 4s –> 3d –> 4p –> 5s –> 4d –> 5p
Give the type of orbital found at each energy level
1 - s
2 - sppp
3- spppddddd
4- spppdddddfffffff
Why is the 4s orbital filled before the 3d orbital
Because 4s is slightly lower in energy
Describe 2 ways of writing electron structure
Spin diagrams - electrons in boxes with arrows
Short hand - uses the noble gas that comes before it.
eg: oxygen is 1s2 2s2 2p4 but can be written as [He] 2s2 sp4. (must use square brackets)
–> This is because helium has 2 electrons in its outer shell so it can substitute the 1s2
When forming ions, is the 4s orbital removed before the 3d orbital
Yes ( apart from copper and chromium )
What is the exception to the rule of filling 4s orbital before 3d orbital
Chromium and copper
Its more stable this way
How many electrons can the d orbital hold
10
(so it could be written as eg: 3d^10)
How many electrons can the f orbital hold
14
In what order do electrons fill subshells
First singularly then pairing up
What is meant by s block elements
The elements in group 1 and 2 have highest energy electron in an s orbital
What is meant by d block elements
Transition metals
What is meant by p block elements
Elements from group 3 to group 7
Define isoelectronic
When either atoms, isotopes or ions ( referred to as species) have the same number of electrons
Define first ionisaton energy
First ionisation energy is the energy required to remove one mole of electrons from one mole of atoms in the gaseous state
[ M(g) → M+(g) + e- ]
Define second ionisation energy
is the energy required to remove one mole of electrons from one mole of 1+ ions in the gaseous state.
[ M+(g) → M2+(g) + e- ]
Give 3 factors that affect ionisation energy
size (distance of the outer shell electrons from the nucleus) , shielding, nuclear charge
What happens to first ionisation energies going down a group
It decreases
Explain why first ionisation energies decreases down a group
Atomic radius (size) increases - increased number of shells so distance from outer shell electrons to nucleus increases
Shell number increases - more shielding between outer shell electron and nucleus due to the inner electrons, so force of attraction decreases
Nuclear charge increases - more protons in nucleus ( but this increase is outweighed by the other factors)