The Reactivity Series of Metals

Question 1

What is a reactivity series?

Answer 1

A list of elements in decreasing/increasing order of reactivity

Question 2

Give the mnemonic for the reactivity series of metals

Answer 2

Please Send Little Charlie’s Monkeys And Zebras In Cages Securely Guarded

Question 3

Give the reactivity series of metals.

Answer 3

Potassium Sodium Lithium Calcium Magnesium Aluminium Zinc Iron Copper Silver Gold

Question 4

Give the reaction of Potassium, Sodium and Lithium with water.

Answer 4

Potassium-burst into lilac flame, floats, melts into a ball, moves
Sodium-melts into a ball, floats, fizzes, moves
Lithium, floats, fizzes, moves

Question 5

Give the reaction of Calcium and Magnesium with water/steam

Answer 5

Calcium-sinks, fizzes, goes white, v. hot to the touch

Magnesium-in strip form w/ water nothing, in powder form, some reaction. w/ steam & boiling water v. vigorous

Question 6

2Lithium/Sodium/Potassium + 2Water =

Answer 6

2Lithium/Sodium/Potassium Hydroxide + Hydrogen

Question 7

Magnesium strip + acid

Answer 7

violent fizzing, heat, colour change, Mg disappears, squeaky pop when gas ignited

Question 8

Zinc + acid

Answer 8

gentle fizzing, quite slow to start

Question 9

Iron + acid

Answer 9

small bubbles, metallic smell

Question 10

Copper + acid

Answer 10

No reaction

Question 11

Define displacement reaction

Answer 11

When a more reactive metal displaces a less reactive metal from a solution of its salt.

Question 12

What is a Thermite Reaction used for?

Answer 12

To produce molten iron to fix railway tracks

Question 13

Give the equation for the Thermite Reaction

Answer 13

Aluminium + Iron (III) Oxide = Aluminium Oxide + Iron

2Al + Fe2O3 = Al2O3 + 2Fe

Question 14

Where is carbon in the reactivity series? How is this useful?

Answer 14

Above Zn, Fe and Cu but below Al. So C can be used to extract Fe from its ore as it is more reactive.
C cannot extract Al or higher because it is less reactive.

Question 15

In the blast furnace what happens?

Answer 15

Iron oxide is reacted with coke (nearly pure carbon) in a 3 step process.

Question 16

Describe the 3 step process in the blast furnace

Answer 16

1)C + O2 = CO2 (exothermic reaction)
2)CO2 + C = 2CO (carbon monoxide)
3)Fe2O3 + 3CO = 3CO2 + 2Fe or sometimes Fe2O3 reacts directly with coke
2Fe2O3 + 3C = 3CO2 + 4Fe

Question 17

Define oxidation and reduction

Answer 17

oxidation- when a substance loses oxygen/electrons

reduction-when a substance gains oxygen/electrons

Question 18

Define oxidising and reducing agents

Answer 18

oxidising agent-gives oxygen/electrons to something else (so is reduced)
reducing agent- receives oxygen/electrons from something else (so is oxidised)

Question 19

Describe 3 problems with iron

Answer 19

1) It rusts
2) If it doesn’t contain enough C(e.g is too pure), it is soft
3) If it contains too much C, it is brittle

Question 20

What is rust? What are the conditions needed?

Answer 20

Hydrated Iron(III) Oxide.
Water and Oxygen (sped up by salt)

Question 21

Name and describe 3 methods of rust prevention

Answer 21

1) Galvanising-coat w/ zinc because zinc is more reactive than iron so reacts with oxygen and water in preference
2) Sacrificial Plating-place bags of a more reactive metal around the iron OR coat the iron in the metal
3) Barrier Methods-stop water and oxygen getting to the iron e.g oil/grease moving parts, coat iron in plastic or paint it

Question 22

Define alloy

Answer 22

A metal with other elements, such as carbon or other metals, added to strengthen it.

Question 23

Why is an alloy stronger?

Answer 23

The particles of the non-metal or other metal interrupt the layers of the metal, meaning they cannot slide over or past each other.

Question 24

Name, give the percentage carbon and give the qualities and uses of 3 types of steel.

Answer 24

1) Low carbon steel-0.1-0.3% carbon, easily shaped and used in car bodies
2) High carbon steel-0.22-2.5% carbon, v. strong, inflexible, brittle and used in bridges
3) Stainless steel-Chromium/nickel added, corrosion resistant, hard and used in cutlery