S3.1 Periodic Table

Question 1

how atomic radii in noble gases was measured

Answer 1

freezing = close as possible = measure

Question 2

periodicity

Answer 2

repeating pattern of a property

Question 3

periodicity trends

Answer 3

• ionisation energy
• electron affinity
• electronegativity
• atomic size/radii
• reactivity

Question 3

Metal properties

Answer 3

• malleable
• lustrous
• high m.p
• high thermal & electrical conductivity
• tendency to losse e-

Question 3

Non metal properties

Answer 3

• brittle
• dull
• low melting points
• low conductivity
• tendency to gain electrons

Question 4

Metalloid properties

Answer 4

• both metal & non metal
• high m.p
• intermediate conductivity
• lustrous
• brittle

Question 5

Atomic size trend

Answer 5

measured as covalent radius in half the distance between nuclei
* size decreases going across period
* size increases going down group

Question 6

Atomic size trend - Period

Answer 6

• decreases
• nuclear charge increases
• larger attractive force between shell and nucleus
• pulls electrons closer => smaller size

Question 7

Ionisation trend - Group

Answer 7

• decreases
• shielding effect = hinders attraction between nucleus & shell
• easier to lose e-

Question 7

Atomic size trend - Group

Answer 7

• increases
• shells increase
• less attraction
• • shielding effect

Question 7

Ionisation trend - Period

Answer 7

• increases
• charge increases = larger attraction
• more difficult to lose e-

Question 7

Ionic Radius

Answer 7

based on nuclear charge to outer electron ratio

Question 8

When answering periodicity questions

Answer 8

SANDI

shielding
attraction
nuclear charge
distance
ionisation

Question 9

Electron affinity

Answer 9

the energy change when 1 mole of electrons is added to 1 mole of gaseous atoms to form 1 mole of gaseous ions

Question 10

Electronegativity Trend - Period

Answer 10

• increases
• nuclear charge increases = greater attractive force

Question 11

Electronegativity Trend - Group

Answer 11

• decreases
• shielding/screening hinders electron attraction

Question 11

Sodium + Water

Answer 11

NaOH + H2
* vigurously
* melts into spehre
* whizzes on surface

Question 11

Lithium + water

Answer 11

LiOH + H2
* effervescene
* floats
* slowly

Question 12

Potassium + Water

Answer 12

• KOH + H2
• more vigurously
• ignie H2
• lilac flame

Question 13

Reactivity trend - Group 1

Answer 13

• increases
• number if shells increases
• easier to lose electrons
• nuclear charge increases = offset by shielding & large size

Question 14

Rubidium/Caesium + Water

Answer 14

RbOH/CsOH + H2
* explosive

Question 15

Reactivity trend - Group 7

Answer 15

• decreases
• shells increase & shileidng
• difficult to gain electron = electron affinity decreases
• greater nuclear charge = offset by shielding
• harder to gain electrons

Question 16

oxidation state

Answer 16

-ate = positive oxidation state
-ide= negative oxidation state

Question 17

Disproportionation

Answer 17

same element is oxidised & reduced simultaneously in the same reaction

Question 18

Acid rain

Answer 18

Corrosion caused by sulfur & nitrogen oxides dissolved in water

Question 19

sulfur oxide origin

Answer 19

sulfur in fossil fuels & volcanic activity

Question 20

nitrogen oxide origin

Answer 20

nitrogen in combustion of fuels & volcanic activity

Question 21

acid rain effects

Answer 21

* ocean acidification * reduces crop yield * errodes building * changes biology of lakes => kills fish * reduce tree growth

Question 22

# dhhdhd electronegativity

Answer 22

the ability of an atom to attract a bonding pair of electrons towards itself in a covalent bond

Question 23

electron affinity

Answer 23

The energy required to add one mole of electrons to one mole of gaseous atoms

Question 24

Is electron affinity endo or exo?

Answer 24

exo, bond making between e and nucleus!

Question 25

How can electron affinity be affected ina. group

Answer 25

goign down group, electron affinity becomes less exo * electrons are further from nucleus * less attractive forces * less energy given out when electrons are taken in

Question 26

Reactivity of halogens

Answer 26

* reactivity decreases down group * atomic radii increase * electron affiity dcereases * lower reactivity

Question 27

Where are the discontinuities in the ionisation trend

Answer 27

group 13 and 15 (change in energy sublevel) => gives proof for sublevels => general trend gives proof for energy level

Question 28

Why does atomic radii differ from ionic radii

Answer 28

Metals tend to lose electrons = ionic radi is smaller than parent atom Non metals tend to gain electrons = Pranet atom (atomic radii) is smaller than ionic radii

Question 29

Using ionisation energies to determine identity of element in Periodic table

Answer 29

look at significant energy differences between ionisation energies

Question 30

where to find metalloids

Answer 30

diagonal from boron * group 14 has two! * period 2 has most non-metals

Question 31

period with most non-metals

Answer 31

period 2

Question 32

noble gas with incomplete p subshell

Answer 32

helium