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Flashcards in List questions Deck (20):
1

Name the main atmospheric pollutants and their danger.

- Carbon monoxide - Poisonous gas.

-  Carbon dioxide - Causes green house effect

 - NO is a respiratory irritant.

- NO2 reacts with unburnt hydrocarbons to produce low level ozone.

- Sulfur dioxide - A contributor to acid rain.

2

Give ways of dealing with polymer waste.

- Sorting polymers and recycling them(through reclamation).

- Use waste polymers as a fuel source to generate electricity.

- Turning polymers into synthesis gas which can be used as chemical feedstock for conversion into useful products.

- Making polymers from renewable material which break down naturally in the environment to form COand water.

3

Give uses of alcohols.

- Ethanol used in alcoholic drink,aftershaves and perfumes.

- Ethanol blended with petroleum to increase octane rating.

- Methylated spirits - Mix of ethanol with small amounts of methanol and dye to produce methylated spirits which is used as a solvent for removing paint or as spirit burners in camping.

- Methanol can be used as a clean burning fuel.

- Methanol used in the feedstock industry.

- Methanol can be formed from biomass, so can be a carbon neutral fuel.

4

In order to perform controlled tests in hydrolysis what should remain the same.

- Use equal amounts,in mol, of each halogenoalkane.

- Use halogenoalkanes of the same chain length.

- Use water bath to ensure constant temperature .

5

Name the uses of CFC's that now can't be done with CFC's.

- Refrigerants 

- Propellants

- Blowing agents

- Solvents( for the dry-cleaning industry)

6

Name the molecules that have now replaced CFC's.

- HFC's - hydrofluoroalkanes.

- HCFC's hydrofluorohydrocarbons .

- butane - (flammable though)

7

Give reasons why 100% percentage yield is usually not achieved.

- Reactions may be at equilibrium and never go to completion.

- Other side reactions may occur, leading to by-products.

- Reactants may not be pure.

- Some products/reactants left in apparatus.

- Seperation and purification may result in loss of product.

8

What factors does the amount of vibration of a molecule after absorbing infrared radiation depend on?

-Bond length

- Bond strength

- The mass of each atom involved in each bond.

9

List the applications of infrared spectroscopy.

- Forensic science

- monitoring the degree of unsaturation in polymers.

- quality control in perfume manufacture

- drug analysis.

10

List the uses of mass spectrometry.

- Identifying unknown compounds.

- To determine the abundance of each isotope in an element.

- Detecting banned substances such as steroids in athletics.

- Analysing molecules in space.

- Detecting traces of toxic chemicals in contaminated marine life.

11

State factors which cause the experimental value of enthalpy of combustion to be less than the true value?

- incomplete combustion 

- heat loss to surroundings.

- specific heat capacity of apparatus not calculated.

12

What can affect the rate of a chemical reaction?

- Catalyst

- Concentration

- Temperature 

- Pressure 

- Surface area

13

List the advantages of using a catalyst in industrial processes:

- Saves energy and therefore costs as well as fuel being burnt.

- Allow processes to occur with less by-products formed hence there is less waste for the companies and less costs in seperation techniques.

14

What are the advantages of enzymes over catalysts?

- Enzymes work at milder conditions such low temperatures and pressures and an optimum pH.

- Enzymes are biodegradable while some catalysts are quite toxic at the end of their industrial lifes.

15

State the conditions for the ammonia process.

- Iron catalyst.

- Temperature of 400 *C.

- Pressures of 200 atmospheres.

16

What are the top three greenhouse gases?

1)H2O

2) CO2

3) Methane

17

What are some strategies to combat climate change?

- Cleaner cars.

- International coorperation ( through agreements to reduce pollution by a certain date/ awerness to public/ have scientists share their ideas.)

- CCS ( carbon capture and storage )

- Alternative energy sources ( solar/wind)

18

Give different uses of CCS.

- Store CO2 in old oil and gas fields.

- Store as carbonates (react CO2 with metal oxide)

- Store CO2 in porous rocks and seafloor.

19

Write out all the steps from the formation of ozone to the destruction of ozone.

- O2 ---> 2O

- O + O2 --> O3 + heat

- O3 + (Uv <320nm ) --> O2 + O

Overall: O3⇔ O2 + O

- O + O3 --> 2O2

20

List the types of catalytic converters and their uses.

- Oxidation catalysts, used in diesel cars. Oxidise carbon monoxide to CO2 and sure hydrocarbons fully react with oxygen.

- Three-way catalysts - fitted into petrol engines:

2NO + 2CO --> 2CO2 + N2