Unit 3.1 - Chemistry In Society/metals Flashcards Preview

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Flashcards in Unit 3.1 - Chemistry In Society/metals Deck (58):
1

When do metallic bonds occur?

Metallic bonds occurs between the atoms of metal elements

2

What are outer electrons?

Delocalised/free to move

3

What does outer electrons being delocalised produce?

An electrostatic force of attraction between the positive metal ions (atoms that have lost an electron to become positively charged)

4

What does the negitive delocalised electrons act as?

A glue, holding atoms together

5

What is the reason for metals being conductors of electricity?

The delocalised electrons

6

What must happen in order for a substance to conduct electricity?

It must allow electrons to flow through it (metals do this well)

7

What happens as one electron moves into the metal from the power supply?

Another electron will jump off the metal

8

Will the metal be changed throughout the conduction of electricity?

No, the metal will remain completely unchanged throughout this and it will always have the same number of electrons

9

Why do Gold, silver and platinum not react with water?

They are all unreactive metals

10

What can explode in water?

Caesium

11

What metals react strongly with water?

The alkali metals, lithium, sodium and potassium

12

What reacts more with acids?

The more reactive metals

13

What reacts more with water?

The more reactive metals

14

What metals will react with and acid and why?

Only metals above hydrogen in the reactivity series will react with acid because all acids contain H+ ions.

15

What metals does acid not have an affect on?

Gold and Platinum

16

Example of

Metal + Acid = Salt + Hydrogen

Magnesium + Hydrochloric acid

Equation - Mg(S) +2HCL(aq)=MgCl2(a)+H2(g)

17

Reactions with Oxygen
Example of
Metal +oxygen =metal oxide

Magnesium reacting with Oxygen to give off a bright light and a exothermic reaction

2Mg(s)+O2(g)=2MgO(s)

18

Why do the reactions of metals make them very useful?

Their use in batteries which provide electricity for our use

19

What is electricity?

Electricity is a flow of electrons that travel along wires

20

How is electricity produced in a battery?

By a chemical reaction taking place in the battery

21

Why do batteries eventually run out?

Because eventually the chemicals in batteries are used up

22

What is the Reactivity series?

A list of elements, listed in order of reactivity starting with the most reactive.

23

The reactivity series

Most reactive - Potassium
- Sodium
- Calcium
- Magnesium
- Aluminum
- Zinc
- Iron
- Nickel
- Tin
- Lead
- Hydrogen
- Copper
- Mercury
- Silver
- Gold
Least reactive - Platinum

24

Cell story

Magnesium and copper are cowboys in the old wild west. To win the heart of a fair lady they challenge each other to a shoot out at high noon. They meet at noon stand back to back walk twelve places and turn and shoot BANG magnesium shoots copper dead with a bullet (electron) and wins the lady (Magnesium was the fastest to REACT

25

What do electrons always go from?

The most reactive metal (oxidation) to the least reactive metal (reduction) and electricity has been made when This happens

26

What is a battery known as in chemistry?

A cell

27

What is a cell made up of?

Two different metals connected by an electrolyte

28

What is an electrolyte?

An ionic solution used to complete the circuit

29

What happens the further apart the metals are in the electrochemical series?

The higher the voltage produced

30

How can electricity be produced in a cell?

By connecting two different metals in a solution for their own ions

31

What is the purpose of the ion bridge?

To complete the circuit

32

What the ion bridge?

A piece of filter paper soaked in salt water or some other ionic solution

33

What is another type of cell?

One which only one metal is involved and the other half of the cell contains SO3 2- ions or l2 with a carbon electrode, in these cells the electrons flow from the non metal to the metal

34

What is a fuel cell?

A device that converts chemical energy from a fuel such as hydrogen into electrical energy through a chemical reaction with oxygen or some other oxidising agent.

35

What is the difference between Batteries and fuel cells?

Fuel cells require an outside source of fuel, while batteries contain the chemicals that they require to produce electricity

36

What batteries are non rechargeable?

Batteries such as the zinc-carbon battery, when the chemicals are used up it should be recycled

37

What happens when the direction of electrical flow in a rechargeable battery reverses?

The chemical reaction that occurred in the battery in the first place reverses making it ready for use again

38

What is an example of a rechargeable battery?

The lead-acid battery which is found in cars

39

Cell story (part 2)
Displacement reactions

After the shoot out magnesium marries the lady and they live together happily ever after

The most reactive metal will ALWAYS win the lady (group ion such as sulphate or nitrate)

This explains the concept of Displacement reactions

40

What happens in Displacement reactions?

The reactive Mayland displaces a metal that is less reactive from solution

41

Example of a Displacement reaction

Mg(S) +CUSO4(aq) =MgSO4+Cu(s)

The most reactive metal always joins to the group ion)(the non metal So4 in this case)

42

What will happen if the group ion is already combined to the most reactive metal?

No reaction will occur
Example - Pb+ZnSO4=no reaction

43

What happens to hydrogen when a metal reacts with acid?

Hydrogen is released

44

What is it known as when substances lost electrons?

Oxidation

45

What is it known as when substances gain electrons?

Reduction

46

OIL RIG

Oxidation Is Loss
Reduction Is Gain

47

What is happening when a metal element is reacting to form a compound?

It's being oxidised

48

A reduction reaction is the opposite of oxidation it is...

The gaining of electrons
-Cu(2+)+2e-=Cu

49

What is a redox reaction?

A reaction where both oxidation and reduction take place.

50

Why are all Displacement reactions redox reactions?

One metal is gaining electrons (reduction) and one metal is losing electrons (oxidation)

51

What do we know about metals that have been found in nature?

They have been there for a long time and have probably reacted with the oxygen In the air and water

52

Are most metals discovered as a pure metal?

No they are mostly discovered as compound which are called ores in this state

53

What metals are found as pure metals and why?

The less reactive metals like gold and Platinum because they are very unreactive

54

What metals are hardest to remove from their ores?

The more reactive the metal, the more difficult to remove from their ores

55

How are less reactive metals removed from their ores?

By heating, some need to be heated with a reducing agent such as carbon monoxide or carbon to remove the oxygen

56

What is a reducing agent?

A substance that can donate electrons

57

How are more reactive metals removed from their ores?

By using electrolysis to remove impurities,

58

How is iron removed from its ores?

In a blast furnace