Atomic structure Flashcards
Electronic configuration etc
What’s the maximum amount of electrons that can fit on the s orbital?
2
What’s the maximum amount of electrons that can fit on the p orbital?
6
What’s the maximum amount of electrons that can fit on the d orbital?
10
What’s the maximum amount of electrons that can fit on the f orbital?
14
How many electrons can the first electron shell contain?
2
How many electrons can the second electron shell contain?
8
How many electrons can the third electron shell contain?
18
How many electrons can the fourth electron shell contain?
32
Why does the 4s subshell need to be filled before the 3D subshell?
Because the 4s subshell is closest to the nucleus and has a lower energy than the 3d subshell
When is the 3d subshell most stable?
When it’s either half full or completely full
What is the ionisation energy?
The amount of energy required to remove electrons from atoms
Why does chromium’s 3d orbital take an electron from the 4s orbital?
Because this allows for less repulsion between the orbitals and helps to make chromium more stable.
Which 2 atoms are exceptions to the orbital rules?
Chromium and copper
Are lower energy levels closer or further away from the nucleus?
closer
Are higher energy levels closer or further away from the nucleus?
further
.
.
Electrons in a shell are found in regions called what?
Atomic orbitals
What is an electron?
A cloud of negative charge. this cloud of negative charge has the shape of the orbital occupied by the electrons.
Which orbitals are filled first?
Orbitals with the lowest energy (closes to the nucleus)
What is each block on the periodic table named after?
The subshell containing the highest energy electron for the elements in that block.
What is the only electron shell involved in chemical reactions?
The outer electron shell
Can the d subshell be involved in chemical reactions?
Yes
What is the exam definition of the first ionisation energy?
The energy needed to remove 1 mole of electrons from 1 mole of atoms in their gaseous state to form 1 mole of 1+ ions(also in their gaseous state)
What is the exam definition of the second ionisation energy?
The energy needed to remove 1 mole of electrons from one mole of 1+ ions in their gaseous state to form one mole of 2+ ions(also in their gaseous state)
The greater the attraction between the outer electrons and the nucleus the greater the what?
The greater the ionisation energy because this attraction makes or more difficult for an electron to be lost
What are the 3 factors affecting ionisation energy?
1) the distance between the nucleus and the outermost electrons
2) the charge on the nucleus
3) shielding
How does the atomic radius affect ionisation energy?
As the atomic radius increases, the force of attraction between the positive nucleus and the outermost electrons decreases. This lowers the ionisation energy
How does the charge of the nucleus affect the ionisation energy?
The greater the number of protons, the greater the force of attraction between the outer electrons and the nucleus
How does shielding affect the ionisation energy?
Electrons in the outer shell are repelled by electrons in the inner shells. This shielding effect reduces the attraction between the outer electrons and the nucleus
Why do successive ionisation energies increase?
Because each time an outer electron is removed , the remaining electrons in the outer shell are pulled slightly closer to the nucleus and the attraction increases . So slightly more energy is required to remove the next electron.
What happens to the first ionisation energy as you go down a group?
It decreases
Why does the first ionisation energy decrease as you go down a group?
-becuse moving down a group, the atomic radius increases. This means that the outer electron shell is further away from the nucleus.
-secondly, going down a group the number of internal energy levels also increase.this means that there’s more shielding between the nucleus and the outer electrons. Weaker attraction, lower ionisation energy
What happens to the first ionisation energies across a period?
The first ionisation energies increase across a period
Why do the first ionisation energies increase across a period?
The nuclear charge increases across a period as the number of protons increases. This increases the attraction between the nucleus and the outer electrons. Because of this, the atomic radius decreases across a period and it’s harder for outer electrons to be lost
What do electrons in the same atomic orbital do to each other?
They repel each other
Which period 2 elements don’t fit the pattern of ionisation energies increasing across a period?
Boron and oxygen
Why doesn’t boron fit the pattern?
For boron, the outer electron needs to be removed from the 2p subshell which has a higher energy than the 2s subshell. So, less energy is required to remove boron’s outer electron in comparison to beryllium.
Why doesn’t oxygen fit the pattern?
2 of the electrons in oxygens p subshell are in the same orbital and so they repel each other. So less energy is required to remove these electrons
