3.5 Metals

Question 1

What is metallic bonding?

Answer 1

The electrostatic attraction between the positive metal ions and the negative delocalised electrons

Question 2

What type of bonding is metallic bonding?

Answer 2

Very strong attraction

Question 3

Why do metals have high melting points?

Answer 3

Lots of energy is needed to break strong metallic bonds

Question 4

Why are metals able to conduct electricity?

Answer 4

Delocalised electrons are free to move through the lattice

Question 5

Why are metals malleable?

Answer 5

The layers of metal ions can slide over eachother

Question 6

What is thermal decomposition?

Answer 6

A reaction where heat energy is used to break down a substance

Question 7

What happens when copper carbonate goes through thermal decomposition?

Answer 7

Produces a black solid (copper oxide), and a colourless gas (carbon dioxide)

Question 8

What is downward delivery?

Answer 8

When a gas sinks to the bottom of a tube

Question 9

What happens when metal reacts with water?

Answer 9

Metal + Water —–> Metal hydroxide + Hydrogen

Question 10

What observations are made when metal reacts with water

Answer 10

• Effervesces (hydrogen produced)
• Solid disappears (used up in reaction)

Question 11

What is observed when Lithium, Sodium and Potassium react with water?

Answer 11

• Solid floats (less dense than water)
• Effervescence (Hydrogen produced)
• Solid moves (effervesces propels)
• Solid disappears ( used in reaction)

Question 12

What flame colour does potassium give off?

Answer 12

Lilac flame

Question 13

Why does reactivity increase down group 1 metals?

Answer 13

• Atoms get bigger and have more shells
• The outer-electron is further from the nucleus
• The attraction between the nucleus and the outer-electron is weaker
• Less energy needed to break the attraction

Question 14

What is the metal + steam reaction?

Answer 14

Metal + Steam —–> Metal Oxide + Hydrogen

Question 15

What is the acid + metal reaction?

Answer 15

Acid + Metal —–> Salt + Hydrogen

Question 16

What observations are made when acid reacts with metal?

Answer 16

• Fizzing (Hydrogen is produced)
• Metal disappears (used up in reaction)

Question 17

What is a redox reaction?

Answer 17

When oxidisation and reduction occur in the same equation

Question 18

What are the lowest in the metal reactivity series?

Answer 18

Au, Ag, Cu

Question 19

What are the middle in the metal reactivity series?

Answer 19

Pb, Fe, Zn

Question 20

What are the highest in the metal reactivity series?

Answer 20

Al, Mg, Ca, Li, Na, K

Question 21

What observations can be made when lithium reacts with water?

Answer 21

It is fast

Question 22

What observations can be made when sodium reacts with water?

Answer 22

Faster, sodium melts

Question 23

What observations can be made when potassium reacts with water?

Answer 23

Fastest, potassium melts, lilac flame

Question 24

Why does group 1 metals get more reactive the further down the group?

Answer 24

• The atoms get bigger, and have more shells
• The outer-electron is further from the nucleus
• The attraction between the nucleus and the outer-electron is weaker
• So less energy is needed to break the attraction

Question 25

Why do metals react with cold water and hot steam to produce different products?

Answer 25

Steam has more energy, so both bonds in the water molecules can break

Question 26

What is the formula for hydrochloric acid?

Answer 26

HCl

Question 27

What is the formula for sulphuric acid?

Answer 27

H2SO4

Question 28

What is the formula for nitric acid?

Answer 28

HNO3

Question 29

What is the formula for phosphoric acid?

Answer 29

H3PO4

Question 30

What two observations can be made from an acid + metal reaction?

Answer 30

- Metal disappears (as it is used up in the reaction - There is fizzing (Because hydrogen gas is produced)

Question 31

What does iron from when oxidised by oxygen?

Answer 31

Iron (III) oxide

Question 32

What three ways prevent rusting?

Answer 32

1) Barrier 2) Sacrificial 3) Galvanising

Question 33

What is the barrier method?

Answer 33

Coating the iron in paint, oil, grease or plastic to prevent the iron coming into contact with water or oxygen

Question 34

What is the sacrificial method?

Answer 34

Attach a block of a more reactive metal to the iron. This works by displacing the iron from rust as soon as rust forms

Question 35

What is the downside to the sacrificial method?

Answer 35

The block of magnesium has to be replaced often

Question 36

What is the galvanising method?

Answer 36

Coating the iron in zinc, which prevents oxygen or water coming into contact with the iron, as well as displacing the iron as it is more reactive

Question 37

What is a reducing agent?

Answer 37

Takes oxygen away from something else

Question 38

What is an oxidising agent?

Answer 38

Gives oxygen to something else

Question 39

What is the alloy steel made up of?

Answer 39

Iron + carbon

Question 40

What is the alloy brass made up of?

Answer 40

Copper + zinc

Question 41

What is the alloy bronze made up of?

Answer 41

Copper + tin

Question 42

Why are alloys harder than pure metals?

Answer 42

They have different sized atoms/ions that prevent the layers of metal ions from sliding over each other. However they are less malleable

Question 43

What is iron used for?

Answer 43

Making steel

Question 44

What is low-carbon steel used for?

Answer 44

Ships, cars, bridges

Question 45

What is high-carbon steel used for?

Answer 45

Tools, knives, screwdrivers

Question 46

What is stainless steel used for?

Answer 46

Cutlery, cooking utensils, kitchen sinks

Question 47

What is copper used for?

Answer 47

Wires, cooking pans, water pipes

Question 48

What is aluminium used for?

Answer 48

Aircraft bodies, power cables