Patterns Of Reactivity- Topic 3

Question 1

what is the General equation for reacting metals with oxygen?

Answer 1

Metal+oxygen—>metal oxide

Question 2

Describe coppers flame, equation and the colour of oxide at end.

Answer 2

Copper+oxygen—>copper oxide
No flame (may see blue), glowing
Oxide= Black on surface

Question 3

Describe iron’s flame, equation and the colour of oxide at end.

Answer 3

Iron+oxygen—>iron oxide
Bright yellow sparks
Dark grey

Question 4

Describe magnesium’s flame, equation and the colour of oxide at end.

Answer 4

Magnesium+oxygen—>magnesium oxide
Bright white light
White powder,ash

Question 5

Give the General equation for metals reacting with water

Answer 5

Metal+water—>metal hydroxide+hydrogen

Question 6

How are the metal and water reactions similar?

Answer 6

All react vigorously
Give off gas & heat
Move across surface

Question 7

How are the metal and water reactions different?

Answer 7

Some react quicker than others
Some produce flames and some don’t
Potassium catches fire + burns with a lilac flame

Question 8

List 3 safety precautions taken when using these metals with water.

Answer 8

Wear safety goggles
Use tongs
Stand back during reaction
If close to others use a screen
Metals are stored under oil

Question 9

List the hazard symbols on each metal jar.

Answer 9

Corrosive
Flammable

Question 10

Why are lithium, sodium + potassium all stored under oil in their jars?

Answer 10

To stop them from reacting with air

Question 11

What observation is taken from calcium when reacted with water?

Answer 11

Produces bubbles + heat. Alkaline.

Question 12

What observation is taken from magnesium when reacted with water?

Answer 12

Reacts slowly, pops.

Question 13

What observation is taken from copper when reacted with water?

Answer 13

Does not react

Question 14

What observation is taken when any metal reacts with water?

Answer 14

All produce hydrogen gas

Question 15

What is produced when metals react with water?

Answer 15

Metal hydroxide + hydrogen

Question 16

Give the word equations for calcium reacting with water.

Answer 16

Calcium+ water—>calcium hydroxide + hydrogen

Question 17

Give the word equations for magnesium reacting with water.

Answer 17

Magnesium+water—>magnesium hydroxide+hydrogen

Question 18

Give the word equations for copper reacting with water.

Answer 18

Copper+water—>no reaction

Question 19

What is the General equation for metals reacted with acid.

Answer 19

Metal+acid—>salt+hydrogen

Question 20

What is usually produced when a metal reacts with an acid?

Answer 20

Hydrogen gas + salt

Question 21

Which metals would you not try putting into acid?

Answer 21

Potassium/sodium/lithium- explosive

Question 22

What happens when aluminium reacts with acid (unusual case)

Answer 22

High up in reactivity series but takes a while to react with acid

With dilute acid (water+acid), it should react fast. A gas will be given off.

Question 23

Why does aluminium take a while to react with acid?

Answer 23

Aluminium oxide layer takes long to dissolve. This protects + stops it from reacting.

Question 24

Why does aluminium resist corrosion?

Answer 24

Forms a layer of aluminium oxide, (protects aluminium + stops it from reacting)

Question 25

Name the reactivity series from most reactive to least reactive.

Answer 25

Potassium Sodium Lithium Calcium Magnesium Aluminium Zinc Iron Copper Silver Gold

Question 26

Name a mnemonic for the reactivity series.

Answer 26

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

Question 27

Name two things about lead.

Answer 27

Very unreactive in cold water Surface of metallic lead is protected by layer of lead oxide.

Question 28

What is the word equations for magnesium and sulfuric acid.

Answer 28

Magnesium+sulfuric acid —>magnesium sulfate + hydrogen

Question 29

What is a displacement reaction?

Answer 29

Eg calcium + zinc sulfate—>calcium sulfate + zinc Gold+iron sulfate—>no reaction A more reactive metal will displace a less reactive metal from its compound. This reaction is observed by colour changes or fizzing or heat being evolved. We call this a displacement reaction

Question 30

Name something silver was used for in the past and why is was considered a good idea.

Answer 30

Used to make coins, unreactive, desirable and malleable metal.

Question 31

What is copper used for and why?

Answer 31

Used to make electrical cables+ wires as it conducts electricity and is cheap to produce.

Question 32

Why do we know so little about the Iron Age?

Answer 32

Iron had corroded/rusted

Question 33

What happens when magnesium mixes with copper sulfate solution. Give the word equation as well.

Answer 33

Copper solid forms and blue solution fades Magnesium+copper sulfate—>magnesium sulfate + copper

Question 34

What happens with an iron nail in water + air?

Answer 34

Rust

Question 35

What happens with an iron nail in dry air?

Answer 35

No rust

Question 36

What happens with an iron nail in water?

Answer 36

A little rust/no rust

Question 37

What happens with an iron nail in water an air+zn wrap

Answer 37

No rust

Question 38

What happens with an iron nail in salty water + air?

Answer 38

Lots of rust

Question 39

What do we need for rust?

Answer 39

Iron, oxygen and water for iron to rust.

Question 40

What is the word equation for rust?

Answer 40

Iron+ oxygen+ water—> hydrated iron oxide (rust)

Question 41

What is another name for rust?

Answer 41

Hydrated iron oxide

Question 42

What do we need for rusting to take place?

Answer 42

Oxygen and water

Question 43

What can we do to prevent iron from rusting!

Answer 43

Paint/oil Plastic coating Galvanising Sacrificial protection

Question 44

Give examples of metals that will rust iron

Answer 44

Copper, silver

Question 45

Give examples of metals that will not rust iron

Answer 45

Zinc, magnesium

Question 46

What is plastic coating?

Answer 46

Prevents air+ moisture from reaching iron

Question 47

What is galvanising?

Answer 47

When iron object is coated in more reactive metal.

Question 48

What can be used to galvanise iron?

Answer 48

Zinc, chromium

Question 49

What is painting/oiling?

Answer 49

Cheapest method of preventing rust

Question 50

What is sacrificial protection?

Answer 50

Used to attach zinc blocks to ships. Zn acts in preference to iron. The water will react with zinc before it reacts with iron as it is more reactive. prevents iron from rusting.

Question 51

Give the best way to prevent a gate from rusting?

Answer 51

Paint it

Question 52

Give the best way to prevent the hull of a ship from rusting?

Answer 52

Sacrificial protection

Question 53

Give the best way to prevent machinery from rusting?

Answer 53

Oil

Question 54

Give the best way to prevent an iron nail from rusting?

Answer 54

Galvanise it