Chapter 7 - Periodicity Flashcards Preview

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Flashcards in Chapter 7 - Periodicity Deck (26)
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1
Q

atomic number

A

(left to right)
it is arranged in order of increasing atomic numbers
every element has atoms with 1 extra electron (than the one before)

2
Q

groups

A

each element in a group has the same number of outer-shell electrons and similar properties

3
Q

periods and periodicity

A

the no. of period = number of highest energy electron shell in an element’s atom.

4
Q

groups 1 and 2 are what block

A

s block

5
Q

groups 3 - 12 are what block

A

d block

6
Q

groups 15 - 18 are what block

A

p block

7
Q

the bottom block is called

A

f block

8
Q

what are group 1 called

A

alkali metals

9
Q

what are group 2 called

A

alkaline earth metals

10
Q

what are group 3-12 called

A

transition elements

11
Q

what are group 15 called

A

pnictogens

12
Q

what are group 16 called

A

chalogens

13
Q

what are group 17 called

A

halogens

14
Q

what are group 18 called

A

noble gases

15
Q

what is first ionisation energy

A

the energy required to remove 1 electron from each atom in 1 mole of gaseous atoms of an element to form 1 mole of gaseous +1 ions.

16
Q

what is ionisation energy

A

how easily an atom loses electrons to form positive ions

17
Q

factors that affect the ionisation energies?

A
nuclear charge (the higher the no. of protons, the higher the attraction between the nucleus and the outer electrons)
atomic radius (increased distance to get to furthest shell, decreasing the attraction)
electron shielding (electrons repel each other, so its called the shielding effect, which reduces the attraction)
18
Q

what is the second ionisation energy

A

the energy required to remove 1 electron from each ion in 1 mole of gaseous 1+ ions of an element to form 1 mole of 2+ gaseous ions.

19
Q

give an example of ionisation energy using helium

A

He has 2 protons and 2 electrons. It loses the first electron and then the other electron actually gets a higher attraction from the proton. This means that the 2nd ionisation energy will be greater than the first.

20
Q

Explain a graph that shows ionisation energies

A

the ionisation energy from one shell to another changes dramatically.

21
Q

Trends of ionisation energy in a period

A
  1. a general increase in first ionisation energy across a period.
  2. a sharp decrease in F.I.E from the end of a period and the beginning of another.
22
Q

Explain the trend down a group

A
  1. atomic radius increases
  2. more inner shells so the amount of shielding increases
  3. nuclear attraction decreases.
  4. F.I.E decreases.
23
Q

Explain the trend across a period

A
  1. Nuclear charge increase
  2. Same shell
  3. Nuclear attraction increases
  4. Atomic radius decreases
  5. F.I.E increases
24
Q

Sub-shell trends

A

Across a group, the ionisation energy will increase till a sub-shell is filled up, and then decrease slightly, then build up again.

25
Q

What is successive ionisation energy

A

An element generally has as many ionisation energies as the number of electrons the element has.

26
Q

What is metallic bonding

A

The molecules have a giant metallic structure
Full of positively charged ions
Surrounded by delocalised electrons.
There are strong electrostatic forces of attraction that exist
between the positively charged ions and the electrons