Using Resources Flashcards

Question

What happens in phytomining to extract metal compounds?

Answer 1

-First, plants are grown on land containing the metal compound we want. -These plants absorb the metal compound and they concentrate it in their tissue. -The plants are then harvested and burned. -At the end, the ash contains a relatively high concentration of the metal compound.

Answer 2

-First, bacteria is mixed with the low grade ore. -The bacteria carry out chemical reactions and they produce a solution called a leachate. -At the end, the leachate contains the metal compound that we want.

Answer 3

-We could displace the metal with a metal with higher reactivity e.g. Iron can displace copper. -Also we could use electrolysis.

Answer 4

-Theses methods do not involve digging, transporting and disposing of large amounts of rock unlike in traditional mining. -And they allow us to economically extract metals from low-grade ores and its important as the Earth's resources of metal ores are limited.

Answer 5

A life-cycle assessment attempts to put a number on the environmental impact of a product.

Answer 6

-Polymers such as plastics are produced using crude oil. -The oil has to be extracted from the ground and then transported to oil refineries and the hydrocarbons have to be separated then cracked and the polymer has to be produced which takes a great deal of energy. -A lot of that energy will be generated by burning fossil fuels which leads to climate change.

Answer 7

-Extracting metals also takes a huge amount of energy. -The ore has to be dug out of the mine and transported for processing, the metal then has to be extracted from the ore and this can produce large amounts of toxic waste products. -Once we have produced our raw materials, we can then manufacture our product, package it and transport it all of these stages will require energy and they may release harmful waste products.

Answer 8

-In the case of a toy, this could involve a large number of batteries and producing batteries releases a large amount of toxic waste.

Answer 9

-Many modern products contain a number of harmful chemicals and these chemicals have to be disposed of carefully and again this may require a lot of energy and it also takes energy to transport used products for disposal.

Answer 10

Using chemicals from crude oil

Answer 11

Wood from trees

Answer 12

-Extracting crude oil can be harmful to habitats e.g. if there is an oil leak and felling trees for wood is also extremely destructive to habitats such as forests. -Both crude oil and wood need to be chemically processed and in both cases this requires a large amount of energy and releases waste products making paper also require huge amounts of water.

Answer 13

-Plastic shopping bags are strong and are often reused as bin liners whereas paper bags tend to tear as they are0n't that strong and are often only used once before being thrown away. (Difference) -At the end of their lives, both plastic bags and paper bags have to be transported either for recycling or to landfills. (Similarity) -Paper bags are often heavier than plastic bags so they can take more energy to transport. (Difference) -Plastic is non-biodegradable and it is not broken down by microorganisms however paper breaks down quickly especially when wet and because plastic bags are non-biodegradable they remain in the environment for a very long time which means they fill up landfills and are a major form of litter. (Difference)

Answer 14

-We can measure the use of water and energy we can also measure the production of some waste products but we cannot always be certain of how damaging these are to the environment which means in some cases we have got to make estimates or value judgments and they may not always be accurate. -Life-cycle assessments can be biased e.g. to support claims by advertisers.

Answer 15

Quarrying produces large amounts of dust and destroys habitats and mining can release harmful chemicals into the environment.

Answer 16

To help save limited resources and energy. Also it will reduce the amount of waste that we produce and have a less harmful effect on the environment.

Answer 17

We melt them and then recast them into different product.

Answer 18

Different metals usually need to be separated before being recycled but that depends on the properties of the final product e.g. scrap steel can be added to iron from a blast furnace and this reduces the amount of iron that we need to extract from iron ore.

Answer 19

The destruction of materials by chemical reaction with substances in the environment.

Answer 20

-First, get three test tubes. -In the first test tube, we have an iron nail in distilled water and the test tube is open to air. -In the second test tube, we have an iron nail and this is also in distilled water however this waster has been boiled so it removes any dissolved air and the water has been covered in oil which prevents any air in the test tube from dissolving in the water. -In the third test tube, we have anhydrous calcium chloride powder which removes any water from the air in the test tube and we have placed a rubber bung on the test tube to prevent any moist air from entering. -Now leave these for several days and them look for any changes. -In test tube 1 there is rust but in test tubes 2 and 3 there is no rust meaning rusting requires both air and water.

Answer 21

By using a barrier between the environment and the materials that we want to protect.

Answer 22

-Grease -Paint -Electroplating (coating the material in a metal) -Galvanising (coating a metal with zinc)

Answer 23

An alloy is a metal blended with other elements and an alloy is a mixture.

Answer 24

By melting our metal, mixing in other elements and then allowing the alloy to cool.

Answer 25

-The atoms form layers in a pure metal meaning the layers of atoms can simply slide over each other whereas atoms in an alloy are different sizes which disrupts the layers and stops them from sliding.

Answer 26

Copper and tin

Answer 27

Because its extremely hard and tends not to corrode

Answer 28

Copper and zinc

Answer 29

Because it can be formed into different shapes to make musical instruments and door handles.

Answer 30

To make it harder

Answer 31

Alloys of iron containing specific amounts of non-metal carbon. Steel also contains other metals.

Answer 32

To make cutting tools such as chisels as it is extremely hard to break but it is also brittle.

Answer 33

To make car bodies as it is soft and easily shaped.

Answer 34

Its an alloy of iron meaning that steel can rust.

Answer 35

We make stainless steel which contains chromium and nickel.

Answer 36

-Hard -Resistant to corrosion

Answer 37

Because they are low density and makes them extremely useful e.g. in aeroplane bodies.

Answer 38

We mix together sand, sodium carbonate and limestone and we the heat this mix in a furnace until it melts. When it cools, it solidifies into any shape that we want.

Answer 39

It has a relatively low melting point which limits its uses.

Answer 40

Because it has a higher melting point than soda lime glass and makes it useful for objects that require heating such as kitchenware and labware.

Answer 41

By melting a mixture of sand and boron trioxide

Answer 42

-Pottery -Bricks

Answer 43

Combining two different materials and we also have the reinforcement which consists of fibres or fragments of one material and the reinforcement is then surrounded by a matrix or binder material.

Answer 44

That they have different properties to the materials in them.

Answer 45

-Very strong and light -Which makes in extremely useful e.g. in cars or in aircraft parts

Answer 46

Steel bars surrounded by concrete and meaning it is extremely strong so it can be used to make buildings.

Answer 47

-Temperature -Pressure -Catalyst

Answer 48

-Thermosoftening polymers melt when we heat them meaning we can reshape them while they are soft so they then can go back to a solid when we cool them back down.

Answer 49

-If we heat the polymer, the intermolecular forces break. Now the polymer strands can separate from each other and the polymer melts.

Answer 50

-If we cool the melted polymer, we reform the intermolecular forces. The polymer goes back to a solid.

Answer 51

-Thermosetting polymers do not melt when we heat them

Answer 52

The polymer chains are linked together by strong crosslinks.

Answer 53

The strong crosslinks are not broken by heat which is why thermosetting polymers do no melt when heated meaning there is no change.

Answer 54

-To make nitrogen-based fertilisers for farming

Answer 55

The Haber process

Answer 56

N₂+3H₂ ⇌ 2NH₃ -With an iron catalyst

Answer 57

Nitrogen can be extracted from the air

Answer 58

Hydrogen can be produced by reacting methane with steam.

Answer 59

The purified nitrogen and hydrogen are passed over an iron catalyst at around 450∘C and 200 atmospheres pressure.

Answer 60

Cool the ammonia to turn it into a liquid which is removed we can then recycle the unreacted nitrogen and hydrogen back over the catalyst.

Answer 61

Exothermic

Answer 62

-We can adjust the temperature and the pressure to shift the position of the equilibrium towards the right hand side (to produce more ammonia). -Since the Haber process is exothermic a relatively cool temperature will shift the equilibrium to the right hand side but a cool temperature makes the reaction slow meaning we have a trade off between the rate of reaction and the position of the equilibrium. -That means 450∘C is a compromise temperature. We get a relatively fast rate and a relatively high yield of ammonia. -Pressure also affects the equilibrium in the case of the Haber process a high pressure will push the equilibrium to the right hand side.

Answer 63

Compounds of nitrogen, phosphorus and potassium

Answer 64

Because these elements improve agricultural productivity meaning they help plants to grow larger and more rapidly.

Answer 65

Large industrial facilities

Answer 66

Ammonium nitrate (NH₄NO₃)

Answer 67

We can use the ammonia produced by the Haber process to produce nitric acid. Then we react the nitric acid with more ammonia to make ammonium nitrate.

Answer 68

-Potassium chloride -Potassium sulfate

Answer 69

It has to be chemically processed

Answer 70

Phosphoric acid and calcium nitrate

Answer 71

It has to be neutralised with ammonia as phosphoric acid contains phosphorus.

Answer 72

Ammonium phosphate

Answer 73

We make a mixture of calcium phosphate and calcium sulfate called single superphosphate.

Answer 74

We make triple superphosphate

Answer 75

School Lab: -We use dilute solutions of ammonia and nitric acid. That is to make them safe to work with. In the lab we produce crystals using a water bath and a Bunsen burner. This requires a lot of heat energy. In the lab, we can only produce a small amount of ammonium nitrate in one go. This is called a batch process. Industry: -The ammonia is used as a gas and the nitric acid is concentrated. This is much more dangerous as the reaction is very exothermic. The heat produced has to be safely removed. This heat is then used in later stages. In industry, some of the energy for evaporation is provided by the exothermic reaction earlier. In industry, the chemical is produced by a continuous process. That means that thousands of kilograms can be produced easily.

Using Resources Flashcards

Paper 2 - C10