Green Chemistry

Question 1

Green Chemistry

Answer 1

The design of the chemical processes and products that reduce or eliminate the use or generation of hazardous substances

Question 2

Chemical processes

Answer 2

Design, manufacture, use, disposal

Question 3

What are the 12 principles of green chemistry

Answer 3

1. Waste prevention
2. atom economy
3. less hazardous chemicals synthesis
4. designing safer chemicals
5. safer solvents and auxiliaries
6. design for chemical efficiency
7. use of renewable feedstocks
8. reduce derivatives
9. catalysis
10. design for degradation
11. real-time population prevention
12. safer chemistry for accident prevention

Question 4

Waste prevention

Answer 4

Prioritise the prevention of waste rather than cleaning up and treating waste after it has been created. Plan ahead to minimise waste at every step.

Question 5

Atom Economy

Answer 5

Reduce waste at the molecular level by maximising the number of atoms from all reagents that are incorporated into the final product. Use atom economy to evaluate reaction efficiency.

Question 6

Less Hazardous chemical synthesis

Answer 6

Design chemical reactions and synthetic routes to be as safe as possible. Consider the hazards of all substances handled during the reaction, including waste

Question 7

Designing Safer Chemicals

Answer 7

Choose the safest solvent available for any given step. Minimise the total amount of solvents and auxiliary substances used, as these make up a large percentage of the total waste created.

Question 8

Design for energy efficiency

Answer 8

Choose the least energy-intensive chemical route. Avoid heating and cooling, as well as pressurised and vacuum conditions (i.e. ambient temperature and pressure are optimal)

Question 9

Use of renewable feedstocks

Answer 9

Use chemicals which are made from renewable (plant based) sources, rather than other, equivalent chemicals originating from petrochemical sources

Question 10

Reduce Derivatives

Answer 10

Minimise the use of temporary derivatives such as protecting groups. Avoid derivatives to reduce reaction steps, resources required, and waste created

Question 11

Catalysis

Answer 11

Use catalytic instead of stoichiometric reagents in reactions. Choose catalysts ti help increase selectivity, minimise waste, and reduce reaction times and energy demands

Question 12

Design for degradation

Answer 12

Design chemicals that degrade and can be discarded easily. Ensure that both chemicals are their degradation products are not toxic, bioaccumulative, or environmentally persistent

Question 13

Real-time pollution prevention

Answer 13

Monitor chemical reactions in real-time as they occur to prevent the formation and release of any potentially hazardous and polluting substances

Question 14

Safer chemistry for accident prevention

Answer 14

Choose and develop chemical procedures that are safer and inherently minimise the risk pf accidents. Know the possible risk of accidents. Know the possible risks and assess them beforehand

Question 15

Atom economy - calculation

Answer 15

• A measure of how many atoms in the reactions end up in the desired product
• high atom economy means few or no waste products (any product other than the desired

Atom Economy = Molar mass of desired products/ molar mass of all reactants x 100