Structure 3.1

Question 1

Period

Answer 1

Rows across Ptable

Question 2

Group

Answer 2

Columns on Ptable

Question 3

What does the period number show

Answer 3

The outer energy level that is occupied by electrons

Question 4

What do elements in a group have in common?

Answer 4

Their valence electrons, this gives similar chemical properties

Question 5

Periodicity

Answer 5

Trends in properties of elements across a period and down a group

Question 6

Trends in properties down a group

Answer 6

Increasing metallic character (G1 elements) decreasing non metallic character (G17 elements)

Question 7

Oxidation state

Answer 7

A number assigned to an atom to show the number of electrons transferred in forming a bond. The charge that atom would have if it was composed of ions.

Question 8

Group 1 name

Answer 8

Alkali metals

Question 9

Group 2 name

Answer 9

Alkali earth metals

Question 10

Group 17 name

Answer 10

Halogens

Question 11

Group 18 name

Answer 11

Noble gases

Question 12

What groups are associated with the s sub-level?

Answer 12

Groups 1 and 2

Question 13

What groups are associated with the p sub-level?

Answer 13

Groups 13-18

Question 14

What groups are associated with the d sub-level?

Answer 14

Groups 3-12 (transition metals)

Question 15

What part of the ptable is the f sub-level associated with?

Answer 15

Lanthanoids and actinoids (2 rows at the bottom)

Question 16

Metalloids

Answer 16

Under boron and then staircase shape down to Polonium

Question 17

Atomic radius (r)

Answer 17

Half the distance between neighbouring nuclei. Can be considered as the distance from the nucleus to the outermost electron.

Question 18

Atomic radius trends across the periods of the ptable.

Answer 18

As the nuclear charge inc so does the electrostatic attraction between the nucleus and the outer electrons resulting in a dec in the atomic radius across a period. Electrons are also being added to the same shell.

Question 19

Atomic radius trends down the groups of the ptable.

Answer 19

The number of occupied electron levels inc down a group so the atomic radius also increases. Inner shells of electrons also provide additional shielding.

Question 20

Nuclear charge

Answer 20

Number of protons

Question 21

Positive ionic radii

Answer 21

Smaller than the atom they are derived from as they have less electrons

Question 22

Isoelectronic positive ionic radii

Answer 22

Dec in size across a period as the number of electrons remains constant but the nuclear charge inc (electrons are pulled closer to nucleus)

Question 23

Negative ionic radii

Answer 23

Larger than their parent atom as they have the same number of protons but more electrons.

Question 24

Isoelectronic negative ionic radii

Answer 24

Decrease in size across a period as the number of electrons is constant but the nuclear charge inc (electrons are pulled closer to the nucleus)

Question 25

Ionisation energy

Answer 25

The enthalpy change when an electron is removed from an atom in a gaseous state.

Question 26

Is the removal of an electron from an atom an endothermic or exothermic process?

Answer 26

Endothermic

Question 27

Ionisation energy trends across the periods of the ptable

Answer 27

Inc in the effective nuclear charge causes an inc in in attraction between the outer electron and the nucleus making it more difficult to remove, leading to higher ionisation energies.

Question 28

Ionisation energy trends down the periods of the ptable

Answer 28

The number of electron shells increases this means the valence electrons are further from the nucleus and are more effectively shielded by the inner electron shells. This weaker attraction to the nucleus makes it easier to remove an electron, leading to lower ionisation energies.

Question 29

Effective nuclear charge

Answer 29

The net positive charge experienced by an electron, taking into account the shielding effect of inner electrons

Question 30

Electron affinity

Answer 30

The enthalpy change when an electron is added to an isolated atom in the gaseous state.

Question 31

Is the addition of an electron to an atom an endothermic or exothermic process?

Answer 31

Exothermic

Question 32

General trends in electron affinity

Answer 32

abs values of ea inc across a period and dec down a group. This is not always a precise trend.

Question 33

Electronegatvity

Answer 33

A relative measure of the attraction that an atom has for a shared pair of electrons when it is covalently bonded to another atom.

Question 34

What group does electronegativity apply to?

Answer 34

Group 18, bc they generally don't form covalent bonds

Question 35

General trends for electronegativity

Answer 35

same as ionisation energy (inc across period and up group)

Question 36

Why does electronegativity inc across a period?

Answer 36

Because of the inc in nuclear charge resulting in an increased attraction between the nucleus and the bond electrons

Question 37

Why does electronegativity dec down a group?

Answer 37

The bonding electrons are further from the nucleus so there is decreased attraction

Question 38

Properties of alkali (g1) metals

Answer 38

Silvery, very reactive, good conductors, low densities (can float), shiny grey when first cut, form ionic compounds with non-metals, react with water to form metal hydroxides and H gas

Question 39

Properties of Halogens (g17)

Answer 39

exist as diatomic molecules, coloured, gradual change through states, very reactive non-metals (higher atomic no. less reactive), form ionic compounds with metals, form covalent compounds with other nm's

Question 40

Metallic character

Answer 40

The tendency to lose electrons and form positive ions (cations).

Question 41

Non-metallic character

Answer 41

The tendency of an element to gain electrons and form negative ions (anions).

Question 42

A Lewis acid can ___ an electron pair

Answer 42

accept

Question 43

A Lewis base can ___ an electron pair

Answer 43

donate

Question 44

Acid rain

Answer 44

rain or other forms of precipitation with a pH lower than normal rainwater (pH 5.6), primarily due to the presence of dissolved sulfur dioxide and nitrogen oxides

Question 45

How is sulfur dioxide produced?

Answer 45

Burning of fossil fuels, particularly coal and heavy oil in power plants used to generate electricity. Industrial processes of smelting (metals are extracted from their ores)

Question 46

How is nitrogen monoxide produced?

Answer 46

Internal combustion engines, the heat from the burning of the fuel causes nitrogen and oxygen in the air to combine.

Question 47

What makes the ocean more acidic?

Answer 47

Carbon dioxide is dissolved by the ocean it reacts with the water to form carbonic acid this then reacts to form H carbonates/carbonates.

Question 48

What do atoms in an uncombined element have an oxidation state of?

Answer 48

0

Question 49

Oxidation state of a simple ion

Answer 49

The same as its charge

Question 50

Oxidation state of all the atoms in a neutral compound add up to...

Answer 50

0

Question 51

Oxidation state of all the atoms in a polyatomic ion add up to...

Answer 51

The charge on the ion

Question 52

What is the usual oxidation state for an element?

Answer 52

The same charge as its most common ion (g1 are +1, g2 are +2)

Question 53

What is the oxidation state of oxygen?

Answer 53

-2, except in peroxides where it is -1 and when bonded to fluorine where it is +2 (as F is more electronegative)

Question 54

What is the oxidation state of chlorine?

Answer 54

-1, except when bonded to F and O as they are more electronegative

Question 55

What is the oxidation state of hydrogen?

Answer 55

+1, except when bonded to G1&2 metals when it forms ionic hydrides (-1)

Question 56

How are binary ionic compounds named?

Answer 56

The cation first, followed by the anion with the suffix -ide

Question 57

How are oxyanions named?

Answer 57

give the oxidation no. of the non metallic element in roman numerals and use the suffix -ate

Question 58

Oxidation in terms of oxidation states

Answer 58

inc in oxidation state

Question 59

Reduction in terms of oxidation states

Answer 59

dec in oxidation state

Question 60

Disproportionation

Answer 60

When the same element is oxidised and reduced simultaneously during the same reaction.