C11 + C12 Reactivity And Dynamic Equilibrium

Question 1

What’s the reactivity series

Answer 1

A list of metals in order of reactivity and the lost reactive at the top

Question 2

When are bubbles of has formed

Answer 2

The metals that react with dilute acids form hydrogen and a salt solution

Bubbles are formed and the more reactive the metal the more bubbles

Question 3

The more easily metal atoms lose electrons ….

Answer 3

The higher the metal in the reactivity series

Question 4

What are displacement reaction

Answer 4

Work only one way, the more reactive metal will react with the substance so the other less reactive metal is displaced

Question 5

Displacement reactions are also…

Answer 5

Redox reactions

Question 6

What are spectator ions

Answer 6

Thus do not change - they don’t lose or gain electrons so can be cancelled out In an ionic equation

Question 7

What’s a redox reaction

Answer 7

A reaction when 1 substance Is oxidised and another is reduced

Question 8

Where are very unreactive metals found

Answer 8

Found naturally in their native states (as in combined elements)

Question 9

What’s extraction

Answer 9

The process of obtaining a metals a metal from these compounds such as rocks

Question 10

What’s an ore

Answer 10

Is a rock that contains enough of a compound to extract a metal for profit

Question 11

How can metal be extracted with displacement reaction

Answer 11

Use a carbon to displace the metal you want, heat it

USED FOR ELEMENTS BELOW CARBON IN THE REACTIVITY SERIES

Question 12

How are metals extracted with electrolysis

Answer 12

Used for extracting metals above carbon on reactivity. Series

Involves passing electricity through a molten ionic compound to decompose it into its elements

A lot of energy is needed to keep metal oxides molten - so expensive

Question 13

What’s bioleaching

Answer 13

Uses bacteria grown on a low-grade ore the bacteria produce a solution containing copper ions called a leachate, copper is extracted from the leachate by displacement using scrap iron, then purified by electrolysis this can be used for metals such as nickel, cobalt, zinc and copper

No high temps needed

Toxic substances can be produced

Question 14

What’s phytoextraction

Answer 14

Involves growing plants that absorb metal compounds, which can be burnt to form an ash and then extract the metal

Very slow

Can extract metals from contaminated soils

Question 15

What’s oxidation and reduction

Answer 15

Oxygen is the gain of oxygen by a substance

Reduction is the loss of oxygen from a substance

ALWAYS OCCUR TOGETHER - called redox reactions

Question 16

When does corrosion happen

Answer 16

When a metal reacts with oxygen it will make the metal weaker over time

The metal is oxidised

Question 17

What’s rusting

Answer 17

The corrosion of iron that requires water as well as oxygen

Question 18

What’s a tarnish

Answer 18

Some metals from a protective oxide layer to prevent further rust

Question 19

Tell me about reversible reactions

Answer 19

Show a double arrow to show forward and backward reactions occur at the same time

Question 20

What’s dynamic equilibrium

Answer 20

Forward and backward reactions are still occurring but the percentages of the reactants and products are no longer changing

Reactions still occurring but remain in balance

Question 21

When does dynamic equilibrium occur

Answer 21

Only occurs in closed systems - no loss of reactants or products

In an open system, gases could escape and so equilibrium could not be achieved

Question 22

Tell me about the Haber process

Answer 22

Involves reversible reaction between nitrogen and hydrogen that can reach a dynamic equilibrium to make ammonia

Conditions chosen to favour the forward reaction and make as much for cheap

Conditions are a temp of 450 C and a pressure of 200 atmospheres

Use of iron catalyst

Question 23

What happens to equilibrium when increasing temperature

Answer 23

In the endothermic direction, equilibrium shifts there

Question 24

Where does the equilibrium position shift when decreasing temperature

Answer 24

In the exothermic direction

Question 25

What happens to equilibriums position when increasing gas pressure

Answer 25

In the direction that forms Fewer gas molecules , as this reduces pressure

Question 26

What happens to the equilibrium position when decreasing gas pressure

Answer 26

In the direction that forms more gas molecules

As this increased pressure

Question 27

What happens when increasing or decreasing a concentration to the equilibrium position shifts

Answer 27

When increasing, In the direction that uses up the substance that has been added

When decreasing, in the direction that froms more of a substance that has been removed

Question 28

What’s bad about electrical waste such as phones and toasters

Answer 28

They are made of precious metals so we need to recycle

Question 29

Tell me some advantages of recycling metals

Answer 29

Natural reserves of metal ores will last longer

The need to mine ores is reduced so less noise and pollution created

Less pollution as less metals are extracted that forms sulfur dioxide when extracted

Many metals need less energy to recycle them than to extract new metal

Less waste metal means less landfill

Question 30

Tell me disadvantages of recycling

Answer 30

Including coats and energy in collecting , transporting and sorting metals to be recycled - not economical

Question 31

What’s a LCA

Answer 31

Life cycle assessment

Question 32

What’s do LCAs do

Answer 32

Work out environmental impact of a product eg disposal, usage, manufacture and getting raw materials

Helps to decide if it’s worthwhile to manufacture and recycle a product - compare the effect of using different materials for the same products eg a bottle glass or plastic