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Flashcards in C7 Deck (82)
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1

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

2

What is the first step in any chemical process?

- converting raw materials into purified feedstocks

3

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

4

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

3.Pharmaceuticals

-drugs, medicines

5.Specialty chemicals

- food flavourings, liquid crystal chemicals in falt screen displays

5

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

- land 

- needs fertilisers

- needs energy to transport and harvest material

6

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%

7

What is the equation for atom economy?

atom economy= mass of atoms in product divided by mass of atoms in the reactants

times 100

eg.calcium oxide=- 56

calcium carbonate =100

56 divided by 100 times 100 = 56%

8

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

9

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

10

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

 

11

How is waste reduced in the chemical industry?

- high atom enconomy 

- increased recycling

-find uses for by- products

12

What is closed loop recycling?

- waste material is collected and used to manufacture the same product

 

13

What is open loop recycling?

this is where waste is collected and used to manufacture another yet lower quality product

 

14

How is harmful waste dealt with by the chemical industry?

- filtered, distilled, centrifuged

- netralised with acids and alkalis

- broken down with microorganisms

15

What are alkanes and what are their properties?

- fuel- gas - petrol

- Phsical properties

- insoluble in water

- 4carbon= gas

-4-17 carbons=liquid

17 or more = solid

Chemical

- burn, falmmable

- strong covalent bonds

- do not react with acids or alkalis

16

What are alkenes?

17

What is a sturated and unsaturated hydro carbon?

-Alkane-  not very reactive 

-saturated

 Alkenes- unsaturated

- double carbo bind

- increases reactivity of a molecule as it can add more hydrogen than alkanes

eg. plastic and polymers made from ethene

18

What are alcohols used for ?

- drink- beer , wine

- as asolvent

- used in cosmetic lotion+perfumes

-feddstocks

-adhesives, foams and wind screen fluid

19

Wgat is the structure and physical properties of alcohols?

 

-liquid at room temperature

- boiling point is less than water

20

What are the chemical properties of alcohols?

- highly flammable

- fuels

- reacts with sodium similary to water as

-oH

- in reactions only the hydrogen in the oh reacts while the other hydrogens are unreactive

21

What are the three ways ethanol acn be produced?

-fermentation

- biotechnology

- chemical synthesis

22

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%

23

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

24

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

25

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

26

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%

27

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

28

What is the structure and names of organic acids?

 

-carboxylic acids

29

How is vinegar made?

ehtanol is oxidised to produce ethanoic acid or vinegar

 

30

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