What are the basic raw materials of the chemical industry?
- crude oil, air water, vegatable materials, rocks and minerals such as metal ores, salt, limestone and gypsum
What is the first step in any chemical process?
- converting raw materials into purified feedstocks
What is a general process for any chemical process?
1. use enrgy or water to prepare raw materials to become feedstocks
2. complete a chemical reaction using a catalyst
3. possibly uses the energy produced by the reaction
4. recycle any unchanged reactions and repeat the process
5 seperate and purify products from by products and waste
What are the products of the chemical industry?
1. Basic organic: chlorine,sodium,hydroxide,sulfuric acid, fertilisers- bulk chemicals
2. Petrochemicals and polymers
-fuels and products like polymers
- dyes , paints and pigments
- food flavourings, liquid crystal chemicals in falt screen displays
How has the chemcial industry tried to make a ne feedstock?
-DuPont- ferments renewable plant material
- makes polymers(Sorona) by converting the fermented plant material into fibres- for clothing
- plant material fermented with bacteruia= malonic acid
-Negatives: biomass issues
- needs fertilisers
- needs energy to transport and harvest material
How do you calculate percentage yield?
percentage yield=actual yield divided by theoretical yield
e.g. Calcium carbonate = calcium oxide + carbon dioxide
calcium carbonate= 40+12+(16 times 3)= 100
calcium oxide = 40 +16= 56
theoretical yield= 56g.
actual yield = 48g.
48 divided by 56 times 100 = 85.7%
What is the equation for atom economy?
atom economy= mass of atoms in product divided by mass of atoms in the reactants
eg.calcium oxide=- 56
calcium carbonate =100
56 divided by 100 times 100 = 56%
What is an example pf the chemical industry implenting one of its aims?
- remove toxic health hazards
- replace toxic chemicals with non- toxic ones
- Monsanto used hydrogen cyanide in weedkiller
- hydrogen cyanide- removed from the process
How is energy generally used in the manufacturing of chemical products?
1. to raise the temperature of the reactants so a reaction begins or continues
2. to haet a mixture of liquids to seperatew and purify products by distillation
3. to dry productsts
4. to process waste
How is the industry trying to become more efficient?
1. prevent loses of steam in leaking valves or stem pipes by installin insulation
3. using the energy from exothermic reactions to generate electric power to contribute to the income of the process
4.using catalyst eg. enzymes
-lower the temperature of some reaction
- less energy
- limit being denatured
How is waste reduced in the chemical industry?
- high atom enconomy
- increased recycling
-find uses for by- products
What is closed loop recycling?
- waste material is collected and used to manufacture the same product
What is open loop recycling?
this is where waste is collected and used to manufacture another yet lower quality product
How is harmful waste dealt with by the chemical industry?
- filtered, distilled, centrifuged
- netralised with acids and alkalis
- broken down with microorganisms
What are alkanes and what are their properties?
- fuel- gas - petrol
- Phsical properties
- insoluble in water
- 4carbon= gas
17 or more = solid
- burn, falmmable
- strong covalent bonds
- do not react with acids or alkalis
What are alkenes?
What is a sturated and unsaturated hydro carbon?
-Alkane- not very reactive
- double carbo bind
- increases reactivity of a molecule as it can add more hydrogen than alkanes
eg. plastic and polymers made from ethene
What are alcohols used for ?
- drink- beer , wine
- as asolvent
- used in cosmetic lotion+perfumes
-adhesives, foams and wind screen fluid
Wgat is the structure and physical properties of alcohols?
-liquid at room temperature
- boiling point is less than water
What are the chemical properties of alcohols?
- highly flammable
- reacts with sodium similary to water as
- in reactions only the hydrogen in the oh reacts while the other hydrogens are unreactive
What are the three ways ethanol acn be produced?
- chemical synthesis
How is ethanol made from plants?
- some parts of the plant fermented
- Cellulose polymers extracted and heated with acid to break it down into glucose
-- glucose= ethanol + carbon dioxide
- lower concentration
of ethanol 14 to 15 %
- can be distilled to increase concentration to 40-50%
Which stages require energy during the production odf ethanol?
- producing fertilisers for plants to grow
- transporting the feedstocks to the factory
- processing the feedstocks
- transporting the ethanol to its point of use
What are the three different energy balances from the feedstocks used to make ethanol?
-sugar cane 8.3-10.2 sugar cane can only br grown in tropical and subtropical climates used in Brazil
sugar beet 1.4- 2.1 used in UK
coen 1.3-1.6 used in US
How can ethanol be produced with biotecnology?
- modifying bacteria so they can breakdown a wide range of sugar
sugar= ethanol + carbon dioxde
- optimun temp. 25-37 and 6-7 pH
How can ethanol be produced using chemical synthesis?
- feedstocks ethene -produced by creating ethane from natral gas
- not renewable
- at 300 celcius 60 to 70 times atmospheric pressure
ethene +steam= ethanol
- atom economy =100%
-- yet a side reaction produces polyethene
- yield 95%
How is the ethanol purified from chemical synthesis?
- 96% ethanol 4% water
placed on zeotites- special; compound with tiny holes in it
- water molecules go through ethanol left behind
What is the structure and names of organic acids?
How is vinegar made?
ehtanol is oxidised to produce ethanoic acid or vinegar
What is the difference between strong and weak acids?
pH1-strong acids- nitric acid
- ionise completely when it dissolves
-pH3 - weak acids - carboxylic acid
only a small part of the molecules
ionises eg. + photo
- both acids react in the expected with metals, alkalis and metal carbonates