Metals

Question 1

Explain the bonding in metals

Answer 1

cations and delocalised electrons held together with electrostatic forces

Question 2

Explain the structure in metals

Answer 2

lattice of cations surrounded by a sea of delocalised electrons

Question 3

Why is it easy to add a different metal atom to a metallic element?

Answer 3

same type of force, easy to replace because electrons are always moving which causes bonds to re-arrange

Question 4

Define alloy

Answer 4

mixture containing at least one metal

Question 5

What are the differences between compounds and mixtures?

Answer 5

Compounds:
- hard to separate
- fixed ration
- fixed mpt
- 2 elements bonded

Mixtures:
- easy to separate
- no fixed ration
- range of mpt depending on ratio
- 2 elements not bonded

Question 6

Which properties of compounds and mixtures do alloys have?

Answer 6

• easy to separate (m)
• no fixed ratio (m)
• 2 elements bonded (c)

Question 7

Why are metals malleable?

Answer 7

because ions can move without breaking metallic bonds

Question 8

Which is more malleable, a pure metals or an alloy?

Answer 8

a pure metal

Question 9

Why are pure metals more malleable than alloys?

Answer 9

In pure metals, layers slide over each other. In alloys, differently sized atoms/ions cannot as easily slide over each other because regular lattice is disrupted

Question 10

How do metals react to form cations?

Answer 10

by losing electrons

Question 11

What determines the reactivity of a metal?

Answer 11

how easily it loses an electron

Question 12

Why does losing electrons require energy in metals?

Answer 12

because energy is required to break the electrostatic forces between outer electrons and nucleus

Question 13

What are the 3 variables that affect force strength? Put them in order from most important to least important.

Answer 13

1) number of electrons being lost
2) distance between nucleus and outer electron (number of occupied energy levels)
3) number of protons in nucleus (atomic number)

Question 14

metal + (cold) water →

Answer 14

metal hydroxide + hydrogen

Question 15

metal + (hot) steam →

Answer 15

metal oxide + hydrogen

Question 16

Mg + H₂O (g)→
What color is the flame?

Answer 16

MgO + H₂
white flame

Question 17

What color is ZnO when hot and when cold?

Answer 17

hot - yellow solid
cold - white solid

Question 18

2Fe + 3H₂O (g)→
What color flame does it burn with?

Answer 18

Fe₂O₃ + 3H₂
orange / red

Question 19

Which elements react with cold water?

Answer 19

K, Na, Li, Ca

Question 20

Which elements react with hot water?

Answer 20

Mg, Zn, Fe

Question 21

Which elements do not react with water?

Answer 21

Cu, Ag, Au

Question 22

Zn + 2AgNO₃ → Zn(NO₃)₂ + 2Ag
What type of reaction is this? Why does the Zn switch places with the Ag?

Answer 22

displacement, Zn displaces Ag because Zn is more reactive.

Question 23

What are the observations of a displacement reaction?

Answer 23

1) solid color change
2) temp. increase (difference in reactivity determines magnitude of charge)
3) solution changes color

Question 24

Define extraction

Answer 24

obtaining a pure metal / element from a compound

Question 25

What do pure metals react with primarily?

Answer 25

O₂ and H₂O

Question 26

What is the reactivity series

Answer 26

K, Na, Li, Ca, Mg, Al, Zn, Fe, Cu, Ag, Au

Question 27

All metals except ______ have been extracted using displacement

Answer 27

Fr (francium)

Question 28

Which metals are extracted using electrolysis?

Answer 28

K, Na, Li, Ca, Mg, Al

Question 29

Which metals are extracted using displacement with Carbon?

Answer 29

Zn, Fe

Question 30

Which metals are extracted using decomposition?

Answer 30

Cu, Ag

Question 31

Which metal doesn’t have to be extracted because it is so unreactive?

Answer 31

Au (gold)

Question 32

Why is displacement with carbon really useful?

Answer 32

1) abundant (common to find)
2) produces a gaseous oxide (easy to separate)

Question 33

What is electrolysis

Answer 33

another form of decomposition

Question 34

Can substances be insulators for electrolysis?

Answer 34

no

Question 35

Which is positive and which is negative in electrolysis?
cathode and anode

Answer 35

cathode is negative
anode is positive

Question 36

What is the liquid in electrolysis called?

Answer 36

electrolyte

Question 37

What is iron ore called?

Answer 37

haematite

Question 38

What is the overall reaction for the extraction of iron? (equation)

Answer 38

2Fe₂O₃(s) + 3C(s) → 3CO₂(g) + 4Fe(s)

Question 39

Why is the extraction of iron harmful for the environment?

Answer 39

• climate change
• acid rain

Question 40

What can acid rain damage?

Answer 40

• trees
• fish
• limestone buildings

Question 41

What are the 3 reactions for the extraction of iron?

Answer 41

1st: C + O₂ → CO₂
2nd: CO₂ + C → 2CO (g) (toxic)
3rd: 3CO (g) + Fe₂O₃ (s) → 2Fe (l) + 3CO₂ (g)

Question 42

Why is the overall reaction for carbon not used?

Answer 42

because it is hard to react 2 solids

Question 43

Why is CO₂ first made when extracting iron?

Answer 43

because the heat speeds up later reactions

Question 44

Name 2 uses of pure iron (freezed in mold)

Answer 44

• trains
• bridges
• (guns)

Question 45

What will happen if Fe is contaminated with SiO₂ during the extraction of iron?

Answer 45

it will become brittle

Question 46

What has to happen before extracting iron?

Answer 46

removing impurities

Question 47

How is CaSiO₃ made?

Answer 47

CaCO₃ -decomposition→ CaO + CO₂

CaO + SiO₂ -neutralisation→ CaSiO₃

Question 48

What is CaSiO₃ used for?

Answer 48

road surfaces

Question 49

What does CaSiO₃ prevent in iron extraction?

Answer 49

prevents O₂ reaching iron