1.6 The Periodic Table

Question 1

periodic table trends

Answer 1

Question 2

blocks

Answer 2

Question 3

Answer 3

Question 4

s-block elements, those found in Group 1 and 2, are metals that form

Answer 4

basic oxides

are reducing agents, so they donate electrons and form cations easily

melting point decreases down the group

Question 5

p-block elements are non-metals that form

Answer 5

acidic oxides

are oxidising agents

Those in Group 6 and 7 can accept electrons and form anions easily.

Their melting point increases down the group.

Question 6

d-block elements are

Answer 6

transition metals

Question 7

oxidising agent

Answer 7

a species that accepts electrons, thereby helping oxidation. It becomes reduced itself in the process

Question 8

which is the oxidising and reducing agent

Answer 8

the oxidising agent is Br2

the reducing agent is Na

Question 9

The reducing agent is

Answer 9

a species that donates electrons, thereby helping reduction. It becomes oxidised itself in the process

Question 10

oxidation and reduction

Answer 10

If a species increases in oxidation number, it is said to be oxidised. If it decreases in oxidation number, it is said to be reduced.

Question 11

Answer 11

protons X

electrons

Question 12

Answer 12

decreases x

increases

Question 13

Answer 13

increases x

decreases

Question 14

Answer 14

gains x

donates

Question 15

Answer 15

donates x

gains

Question 16

Answer 16

Question 17

Answer 17

Question 18

Answer 18

Question 19

Answer 19

Question 20

flame test colours

Answer 20

Question 21

Practical method for flame tests

Answer 21

To carry out a flame test, dip a wire loop into concentrated hydrochloric acid and then hold in a roaring flame of a Bunsen burner to remove any contaminants.

Then dip the loop in the compound to be tested and hold again in the roaring flame. It is important that the flame has no colour so the colour of the compound can be seen. Observe any colour shown by the compound.

Question 22

Oxides are formed when

Answer 22

the s-block metals come into contact with oxygen or air

Question 23

group 1 oxidation

Answer 23

Question 24

group 2 oxidation

Answer 24

Question 25

All the oxides formed are basic. This means they react with acid to give

Answer 25

a salt and water

Question 26

Group 1 elements react with water

Answer 26

metals react more vigorously as you go down the group

Question 27

Group 2 elements react with water

Answer 27

Question 28

Answer 28

Question 29

Answer 29

All precipitates are white. Write ionic equations for the formation of an insoluble salt

Question 30

⚛️ Reactivity Trends in Group 1 and Group 2

Answer 30

Question 31

Answer 31

Question 32

When heated, Group 2 carbonates undergo thermal decomposition

Answer 32

to produce an oxide and carbon dioxide gas.

Question 33

Group 2 Carbonates As you move down the group, this reaction happens more slowly as carbonates are more thermally stable the further down the group they are.

Answer 33

Question 34

Metal hydroxides

Answer 34

also decompose on heating, but they form an oxide and water

Question 35

Answer 35

Question 36

Solubility of Group 2 Hydroxides

Answer 36

Question 37

Solubility of Group 2 Sulfates

Answer 37

The trend here is the opposite. Solubility decreases down the group. So, whilst magnesium sulfate is soluble, barium sulfate forms an insoluble white precipitate.

Question 38

Answer 38

Question 39

🧪 Basic Character of Group 1 and Group 2 Oxides and Hydroxides

Answer 39

Question 40

⚖️ Base Strength and Group Trends

Answer 40

Question 41

Answer 41

Question 42

volatility group 7

Answer 42

the tendency to form a gas at room temperature, decreases down the group as does the melting point because the intermolecular forces holding the diatomic elements together get stronger as the atom gets bigger The increased number of electrons in the atom, as you go down the group, contribute to the increase of induced dipole – induced dipole interactions that hold the molecule together.

Question 43

reactivity group 7

Answer 43

The reactivity also decreases as you go down the group. This is because the oxidising power of the elements also decreases. This is due to the fact that larger atoms are less able to attract electrons.

Question 44

Answer 44

Question 45

halogen + sodium

Answer 45

Question 46

halogen + iron

Answer 46

Question 47

Answer 47

Question 48

silver halide precipitate ionic equation

Answer 48

Question 49

First add dilute nitric acid, HNO3(aq) followed by aqueous silver nitrate, AgNO3(aq) testing with aqueous ammonia, NH3, can be used to distinguish colour

Answer 49

Question 50

The displacement reactions are another set of reactions that we can use to show how reactivity of the halogens decreases down the group. A more reactive halogen will displace a less reactive one from a solution of one its salts.

Answer 50

Question 51

chlorine add bromine ionic equation

Answer 51

Question 52

Answer 52

Question 53

chlorine forms equillibrium with water

Answer 53

It needs to be added at concentrations below 1 part per million (ppm) in order to be beneficial. There is no real opposition to the addition of chlorine to water since it makes water safe to drink. Fluoride is added to toothpaste and water as it strengthens tooth enamel helping to prevent decay. It can also strengthen bones and prevent osteoporosis. Again, it needs to be added at concentrations below 1 part per million (ppm) in order to be beneficial. Higher doses in water can be harmful and discolour teeth. This is called fluorosis. Fluorine has also been linked to bone cancers and thyroid problems. Adding fluorine to water is therefore more controversial. Many people feel it is forced mass medication, taking away freedom of choice. Others argue that toothpaste provides sufficient doses of fluorine so adding it to the water is unnecessary.

Question 54

form copper(II) sulfate crystals soluble salt formation in which crystallisation is used to obtain the solid.

Answer 54

Question 55

Answer 55

Question 56

Insoluble salts are made by

Answer 56

precipitation reactions in which an insoluble solid is formed when two solutions are mixed.

Question 57

Answer 57

Question 58

Gravimetric analysis means

Answer 58

using the mass of the substance produced to quantify it. In this experiment an unknown chloride is going to be used and gravimetric analysis will allow us to calculate its molar mass and concentration in solution.

Question 59

Gravimetric analysis method

Answer 59

Question 60

gravimetric analysis calculations

Answer 60

Question 61

Answer 61

Question 62

Qualitative analysis

Answer 62

is the process by which unknown salts are identified using chemical tests. Again, a video of this practical is available below.