Metals

Question 1

Describe the structure and bonding in metals

Answer 1

Metals consist of a lattice of positive ions held together in a sea of delocalised, mobile electrons by strong metallic bonds

Question 2

Give 5 Physical Properties of Metals

Answer 2

1. High melting and boiling points
2. High density
3. Malleable and Ductile
4. Good conductor of heat and electricity
5. Soft

Question 3

Metals have _______ melting and boiling points because ______ (Explain fully)

Answer 3

high;

1. metals consist of a lattice of positive ions held together in a sea of delocalised, mobile electrons by
2. strong metallic bonds which
3. require large amounts of energy to overcome. 4.Therefore they generally have high melting and boiling points

Question 4

Metals have generally _____ densities because _______

Answer 4

high; the atoms are closely packed with little space between them, leading to a considerably large mass per unit volume.

Question 5

Metals are _______ (ablility to be reshaped) and _____ (ability to be strwen into wires) because _______

Answer 5

Malleable; Ductile; the lattice of positive ions have a orderly arrangement which allows layers of ions to slide over one another without breaking when a force is applied

Question 6

Metals are _______ conductors of heat and electricity because ________

Answer 6

good; of the presence of delocalised mobile electrons that aid in transferring thermal energy and act as charge carriers.

Question 7

What is an alloy?

Answer 7

Mixture of atoms of one metal with atoms of other elements.

Question 8

Why are Alloys harder than the pure metals themselves?

Answer 8

1. Alloys consist of atoms of other elements which are a 2.different size compared to the metal atoms,
2. disrupting the orderly arrangement of the positive lattice.
3. Thus, when a force is applied the layers of atoms are unable to slide over one another, causing it to be hard.

Question 9

Give the constituents of Brass, and its uses

Answer 9

Copper and Zinc,

Decorative ornaments, Musical instruments

Question 10

Give the constituents of Stainless Steel, and its uses

Answer 10

Iron Chromium Nickel Carbon

Cutlery, Medical instruments, Pipes in chemical industries

Question 11

Give the constituents of solder, and its uses

Answer 11

Lead Tin

Joining metals

Question 12

Give the constituents of Pewter, and its uses

Answer 12

Decorative ornaments

Question 13

Give the order of metals in the reactivity series

Answer 13

K
Na
Ca
Mg
Al
C
Zn
Fe
Sn
Pb
H
Cu
Ag
Au
Pt

Question 14

Give the observations (and products) of the folllowing:

Potassium + Water

Answer 14

1.Reacts very violently with
2.Effervescence of colourless gas
(Potassium Hydroxide and Hydrogen Gas are produced)
3.Hydrogen Gas might catch fire and burn with lilac flame

Question 15

Give the observations of the folllowing:

Sodium + Water

Answer 15

1.Reacts violently with
2.Effervescence of colourless gas
(Sodium Hydroxide and Hydrogen Gas are produced)
3.Hydrogen Gas might catch fire and burn with yellow flame

Question 16

Give the observations of the folllowing:

Calcium + Water

Answer 16

1.Reacts readily with
2.Effervescence of colourless gas
(Calcium Hydroxide and Hydrogen Gas are produced)

Question 17

Give the observations of the folllowing:

Magnesium + Water

Answer 17

1.Reacts very slowly with cold water
2.Slow bubbling of colourless gas
(Magnesium Oxide and Hydrogen Gas are produced)

Question 18

Give the observations of the folllowing:

Zinc/Iron/Lead/Copper/Silver + Water

Answer 18

No reaction

Question 19

Give the observations (and products) of the folllowing:

Potassium/Sodium + Acid

Answer 19

Reacts Explosively. Reaction should not be carried out in the lab. (products are Potassium salt and Hydrogen gas)

Question 20

Give the observations (and products) of the folllowing:

Calcium + Acid

Answer 20

1.Reacts very rapidly
2.Effervescence of colourless gas
(Calcium salt and Hydrogen gas are produced)

Question 21

Give the observations (and products) of the folllowing:

Magnesium + Acid

Answer 21

1.Reacts rapidly
2.Effervescence of colourless gas
(Magnesium salt and Hydrogen gas are produced)

Question 22

Give the observations (and products) of the folllowing:

Zinc + Acid

Answer 22

1.Reacts moderately fast
2.Effervescence of colourless gas
(Zinc Salt and Hydrogen gas are produced)

Question 23

Give the observations (and products) of the folllowing:

Iron + Acid

Answer 23

1.Reacts slowly
2.Effervescence of colourless gas
(Iron Salt and Hydrogen gas are produced)

Question 24

Give the observations (and products) of the folllowing:

Lead/Copper/Silver + Acid

Answer 24

No reaction

Question 25

Give the observations (and products) of the folllowing: | Magnesium + Steam

Answer 25

1. Reacts violently 2. with a white glow 3. forming a white powder (Magnesium Oxide and Hydrogen are formed)

Question 26

Give the observations (and products) of the folllowing: | Zinc + Steam

Answer 26

1. Reacts readily 2. forming a yellow powder when hot, white when cold (Zinc Oxide and Hydrogen are formed)

Question 27

Give the observations (and products) of the folllowing: | Iron + Steam

Answer 27

1. Reacts slowly with red hot iron (must be heated for reaction to proceed) (Forms Iron (II, III) Oxide Fe₃O₄ and Hydrogen Gas)

Question 28

Give the observations (and products) of the folllowing: | Lead/Copper/Silver + Steam

Answer 28

No reaction occurs

Question 29

(Pure) Oxides of metals below carbon in the reactivity series can be _______ by carbon. The products produced are _______ and _______

Answer 29

Reduced; Metal and carbon dioxide

Question 30

(pure) Oxides of metals below Hydrogen in the reactivity series together with _____ and ______ can be _______ by hydrogen. The products produced are _______ and _______

Answer 30

FeO, PbO; reduced; metal and water

Question 31

(Pure) | Silver oxide _______ upon hearing to form _______ and _____

Answer 31

Decomposes; silver metal and water

Question 32

(pure) A _____ reactive metal can ______ a _____ reactive metal from it's _________. This is known as a ________ and _______ reaction

Answer 32

More; Displace ; Less; Salt Solution

Question 33

(pure) | How does one extract metals above Carbon in the reactivity series?

Answer 33

Electrolysis of molten salt

Question 34

(pure) | How does one extract metals below Carbon in the reactivity series?

Answer 34

Reduction using either carbon or hydrogen depending on the position of the metal

Question 35

Give three advantages of recycling metals

Answer 35

1. conserves the limited resources of metal ores: finite and will run out 2. Save costs of extracting metals from ores 3. Reduce environmental issues: recycling produces less waste, air and land pollution

Question 36

Give three disadvantages of recycling metals

Answer 36

1. For cheap metals, recycling might be more expensive than extraction 2. Recycling of some metals can cause air pollution: smelting used to extract Pb from old car batteries can release toxic fumes 3. Resistance to adopting recycling as a lifestyle

Question 37

What are the three materials added to the blast furnace in the extraction of iron

Answer 37

Haematite (Fe₂O₃) Coke (C) Limestone (CaCO₃)

Question 38

Give the 5 equations involved in the extraction of iron with state symbols

Answer 38

1. C(s) + O₂(g) --> CO₂ (g) 2. CO₂(g) + C(s) --> 2CO(g) 3. Fe₂O₃ (s) + 3CO(g) --> 2Fe(l) + 3CO₂(g) 4. CaCO₃ (s) --> CaO(s) + CO₂(g) 5. CaO(s) + SiO₂(s) --> CaSiO₃ (l)

Question 39

(pure) Steel is an ______ of ______. What are the three types, properties and uses of steel?

Answer 39

Alloy; Iron 1. High carbon steel, strong but brittle, to make tools like knives, hammers etc 2. Low carbon steel, softer and more easily shaped, to make car bodies and machinery 3. Stainless steel, does not rust, used to make cutlery and surgical instruments.

Question 40

(pure) Cast iron contains ________ which makes it _____

Answer 40

Impurities; brittle

Question 41

(pure) | How are impurities removed from cast iron?

Answer 41

1. Melted and poured into a large container 2. Pure oxygen at high pressure is blown into the molten iron to oxidize all impurities 3. Carbon and sulfure are oxidised to carbon dioxide and sulfur dioxide that escape as gases 4. Silicon and Phosphorous form oxides 5. Calcium carbonate is added, which decomposes to form Calcium Oxide, reacting with the silicon dioxide and Phosphorous oxide to form slag 6. The pure iron is left behind

Question 42

(pure) | How is steel made from pure Iron?

Answer 42

It is mixed with carbon in varying amounts depending on the type of steel desired. Other metals like chromium and nickel can also be added to give the special properties of steel.

Question 43

What is Rusting, and the conditions needed for it to occur?

Answer 43

The slow oxidation of iron to form hydrated iron (III) oxide. Oxygen and water are necessary

Question 44

What are the 3 methods of preventing rust?

Answer 44

1. Using a coating that acts as a barrier around the metal 2. Using a more reactive metal (sacrificial protection) 3. Using alloys

Question 45

How does coating iron prevent corrosion? What is the disadvantage of this method?

Answer 45

The coating acts as a barrier against the oxygen in air, preventing the metal from coming into contact with it and rusting. The disadvantage is that if the coating is damaged or scratched, the iron underneath is exposed and will rust.

Question 46

Rusting in ships is prevented by fixing ______ to the shops hull. Whereas blocks of ________ are attached to underground iron pipes to prevent rusting.

Answer 46

Bars of zinc; | Magnesium

Question 47

What is galvanising?

Answer 47

The coating of iron or steel with zinc to prevent rusting.

Question 48

What is the advantage of galvanising iron?

Answer 48

Zinc is more reactive than iron, so even if the layer is damaged, the iron will not rust.