Chemistry OCR 1.2.1 Evidence of Shells

key terms and concepts

?
What is the first ionisation energy of an element?
The energy required to remove one electron from EACH atom in one mole of GASEOUS ATOMS to form one mole of gaseous 1+ ions.
1 of 11
How would the first ionisation energy of Sodium, Na(g), be shown in an ionic equation.
Na(g)--->Na+(g) + e-
2 of 11
How does the atomic radius affect the nuclear attraction between the electrons in the outer shell and the positive nucleus?
The GREATER the atomic radius, the SMALLER the nuclear attraction experienced by the outer electrons.
3 of 11
How does the nuclear charge affect the nuclear attraction experienced by the outer electrons?
The GREATER the nuclear charge, the GREATER the attractive force on the outer electrons.
4 of 11
What is electron shielding?
the repulsion between electrons in different inner shells.
5 of 11
How does electron shielding affect the nuclear attraction experienced by the outer electrons?
The inner shells of electrons repel the outer-shell electrons. The more inner shells there are, the larger the shielding effect and the smaller the nuclear attraction experienced by the nuclear electrons.
6 of 11
Why are electrons in the outer shell of an electron removed first?
They are furthest away from the nucleus and require the least ionisation energy. They experience the least nuclear attraction.
7 of 11
Define successive ionisation energies
a measure of the energy required to remove each electron in turn. (i.e the second ionisation energy is the energy required to remove one electron from each ion in one mole of gaseous atoms to form one mole of 2+ gaseous ions)
8 of 11
What would the ionic equation or the 3rd ionisation energy of Lithium, Li(g), be?
Li2+(g)---> Li3+(g) + e-
9 of 11
Why is each successive ionisation energy larger than the one before?
As each electron removed, there is less repulsion between the electrons and each shell will be drawn closer to the nucleus. As the distance of each electron from the nucleus decreases, the nuclear attraction increases.
10 of 11
Card 10 continued
More ionisation energy is needed to remove each successive electron
11 of 11

Other cards in this set

Card 2

Front

How would the first ionisation energy of Sodium, Na(g), be shown in an ionic equation.

Back

Na(g)--->Na+(g) + e-

Card 3

Front

How does the atomic radius affect the nuclear attraction between the electrons in the outer shell and the positive nucleus?

Back

Preview of the front of card 3

Card 4

Front

How does the nuclear charge affect the nuclear attraction experienced by the outer electrons?

Back

Preview of the front of card 4

Card 5

Front

What is electron shielding?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Evidence of shells resources »