Topic 4:Inorganic Chemistry

Question 1

What happens to elements as you go down grp 2?

Answer 1

There is increasing shielding.

Question 2

When you do down grp 2 what happens to nuclear charge? And why?

Answer 2

the nuclear charge increases because each element has more protons in its nucleus.

Question 3

What happens to ionisation energy as you go down grp 2?

Answer 3

It decreases.

Question 4

How does reactivity in grp 2 occur?

Answer 4

They lose their 2 outer electrons.

Question 5

What happens to reactivity down grp 2? Why?

Answer 5

It increases down the grouo,because the atomic radius increases and there is increased shielding due to additional inner shells. Although the nuclear charge increases, the shielding effect and increased atomic radius outweigh this, resulting in a weaker electrostatic attraction between the nucleus and the outer electrons. This makes it easier to remove the outer electrons as the ionization energy decreases.

Question 6

What do grp 2 elements produce when they react with water?

Answer 6

Metal hydroxide(aq) and hydrogen(g)

Question 7

What do you see when you add water to barium in a test tube?

Answer 7

Lots of bubbles.

Question 8

What is formed when grp 2 elements react with chlorine?

Answer 8

Solid white chlorides.

Question 9

Describe the reaction of Mg and water.

Answer 9

Mg + 2H₂O → Mg(OH)₂ + H₂ (slightly soluble)

Reaction is slow at room temperature; more vigorous with steam.

Question 10

Describe the reaction of Ca and water.

Answer 10

Ca + 2H₂O → Ca(OH)₂ + H₂

More vigorous than magnesium.

Question 11

Describe the reaction of Ba and water.

Answer 11

Ba + 2H₂O → Ba(OH)₂ + H₂

Very vigorous reaction, producing a strong alkaline solution.

Question 12

Describe the reaction of Magnesium Oxide and water.

Answer 12

MgO + H₂O → Mg(OH)₂ (slightly soluble in water, forms a weak alkali)

Question 13

Describe the reaction of Calcium Oxide and water

Answer 13

CaO + H₂O → Ca(OH)₂ (forms a strong alkali)

Question 14

Describe the reaction of Barium Oxide and water

Answer 14

BaO + H₂O → Ba(OH)₂ (forms a strong alkali)

Question 15

What do the oxides of Group 2 metals react with water to form?

Answer 15

Metal Hydroxides.

Question 16

Why is Berrylium hydroxide an exception?

Answer 16

It is insoluble and doesn’t react with water.

Question 17

What happens to the alkanity of grp 2 metal hydroxides down the grp

Answer 17

The alkalinity increases down the group because the hydroxides get more soluble.

Question 18

What do grp 2 metal hydroxide and oxide form when they react with dilute acid?

Answer 18

Group 2 metal hydroxides and oxide react with dilute acids to form the corresponding salt(aq) and water(l).
Mg(OH)₂ + 2HCl → MgCl₂ + 2H₂O

Question 19

Describe the trend of the solubility of Grp 2 metals hydroxides.

Answer 19

Solubility increases down the group,as the compound anion contains singly charged negative ions.

Question 20

Describe the trend of the solubility of Grp 2 metals sulfates.

Answer 20

Solubility decreases down the group, as the compound anion contains doubly charged negative ions.

Question 21

Barium sulfate is insoluble. True or False.

Answer 21

True.

Question 22

Magnesium is sparingly soluble, true or false.

Answer 22

True.

Question 23

Decrube the Trends in Thermal Stability of Nitrates and Carbonates.

Answer 23

Thermal stability increases down the group for nitrates and carbonates.

Question 24

Describe the size of cation and charge density down a group.

Answer 24

The futher down a group, the larger the cations, the lower the charge density.

Question 25

How do cations distort anions?

Answer 25

By polarising the anions.

Question 26

The greater the distortion...

Answer 26

the less stable the compound.

Question 27

The larger the cation...

Answer 27

the lesser the distortion.

Question 28

The lower the charge desnity

Answer 28

the more spread out the charge on the ion is.

Question 29

Why are grp 2 compounds less thermally stable than grp 1 compounds?

Answer 29

Group 2 cations have a +2 Charge. The greater the charge, the greater the distortion, and so the less stable the carbonate/nitrates compound becomes.

Question 30

Group 1 carbonates decompose at much higher temperatures, except

Answer 30

Li₂CO₃ which decomposes to Li₂O and CO₂.

Question 31

Group 1 carbonates are

Answer 31

Thermally stable

Question 32

Group 2 carbonates decompose to form

Answer 32

a group 2 oxide(solid) and carbon dioxide(g)

Question 33

Group 1 nitrates decompose to form

Answer 33

a grp 1 nitrite(solid) and oxygen gas. Nitrite-NO2

Question 34

Group 1 nitrates exception is

Answer 34

LiNO₃.which decomposes on heating to form Li₂O, NO₂, and O₂.

Question 35

Grpup 2 Nitrates decompose to form

Answer 35

the oxide,(s), nitrogen dioxide (g) and oxygen(g).

Question 36

How do you test for the thermal stability of Nitrates?

Answer 36

-How long ut takes until a certain amount if **oxygen** is produced[enough to relight a glowing splint] -How long it takes until an amount of NO₂[brown gas] is produced. Should be done in a fume cupbaord as brown gas is toxic.

Question 37

How to test thermal stability of carbonates.

Answer 37

How long it takes for an amont of carbon dioxide to be produced.

Question 38

How do you test for carbondioxid

Answer 38

Using lime water[Ca(OH)2], it turns cloudy with CO2

Question 39

What is transition?

Answer 39

This is movement of electrons between energy levels.

Question 40

Descrine how flame colours are formed

Answer 40

When a metal ion is heated, its electrons absorb energy and move to a higher energy level. The electrons then return to their ground state, releasing energy in the form of light. The wavelength of this light corresponds to a specific color in the visible spectrum.

Question 41

How do you do a flame test?

Answer 41

1. Clean a nichrome/platinum wire loop by dipping it in conc hydrochloric acid and then placing it in a Bunsen burner flame until no color appears. Ensures no contamination. 2. Dip the clean wire loop into a sample of the solid metal compound. 3. Hold the loop in the blue (hottest) part of a roaring Bunsen burner flame. Prevents interference from the yellow flame. 4. Observe the flame color and compare it to known metal ion colors.

Question 42

Flame colour of Li

Answer 42

Red

Question 43

Yellow flame colour

Answer 43

Na

Question 44

K flame colour

Answer 44

Lilac

Question 45

Rb flame colour

Answer 45

Red

Question 46

Blue flame colour

Answer 46

Cs

Question 47

Ca colour

Answer 47

Brick red

Question 48

Crismson colour

Answer 48

Sr

Question 49

Ba colour

Answer 49

Green

Question 50

What is the trend for the melting and boiling points for group 7.

Answer 50

Melting and Boiling points increase down group 7

Question 51

What is the reason for the increase of mp and bp down group 7?

Answer 51

As you go down Group 7, electron shells increase. Increasing london forces between halogen molecules means more energy is required to overcome these intermolecular forces, and so mp and bp increase.

Question 53

Flourine at RTP

Answer 53

Pale yellow, gas.

Question 54

Chlorine at RTP

Answer 54

Green gas

Question 55

Bromine at RTP

Answer 55

Red-brown, liquid.

Question 56

Iodine at RTP

Answer 56

Grey, solid. Sublimes to purple vapour.

Question 57

Because halogens are non polar.

Answer 57

They have low solubility.

Question 58

Halogens dissolve easily in

Answer 58

Organic solvent like hexane.

Question 59

What is the colour of chloeine in water?

Answer 59

Virtually colourless

Question 60

What is the colour of bromine in water

Answer 60

Yellow/orange

Question 61

What is the colour of Iodine in water

Answer 61

Brown

Question 62

What is the colour of chlorine in hexane?

Answer 62

Virutually Colourless

Question 63

What is the colour of bromine in hexane.

Answer 63

Orange/red

Question 64

What is the colour of Iodine in hexane

Answer 64

Pink/violet.

Question 65

What is the chemistry of fluorine

Answer 65

It is a toxic gas

Question 66

What us the chemistry of Astatin

Answer 66

It is radioactive and decays quickly.

Question 67

Describe the trend of electronegativity down group 7. Why?

Answer 67

It decreases down the group. Atomic radius increases → outer electrons further from nucleus. More shielding by inner electron shells. Weaker nuclear attraction for bonding electrons.

Question 68

What is Electronegativity?

Answer 68

It is a measure of how well an atom attracts electrons in a covalent bond.

Question 69

Describe the trend of Reactivity down group 7. Give reason.

Answer 69

Reactivity decreases down the group. Atomic size increases → outer electrons are further from the nucleus. Inner shells increases, causing more shielding reducing effective nuclear attraction.

Question 70

How do halogens react?

Answer 70

gaining an electron in their p sub shell.

Question 71

Halogens are reduced which means they are

Answer 71

Oxidising agents.

Question 72

What is a displacement reaction?

Answer 72

A type of reaction where one element replaces another in a compound.

Question 73

In a displacement reaction a more reactive halogen will replace

Answer 73

a less reactive halode in a solution.

Question 74

Halidebis used to describe the

Answer 74

Negative ion.

Question 75

Chlorine will displace

Answer 75

Bromide and Iodide ions.

Question 76

Bromine will not displace chloride ions but

Answer 76

Iodide ions.

Question 77

Iodine will not displace

Answer 77

Either chloride or bromide ions, suggesting that oxidising strength decreases down the group.

Question 78

What type of reaction is between halogens and halides.

Answer 78

A redox reaction.

Question 79

The thing that is displaced becomes

Answer 79

Oxidised

Question 80

The thing that does the displacing becomes

Answer 80

Reduced

Question 81

When an halide is displaced

Answer 81

an halogen is formed.