Submission of Proposal under Star College Scheme

6. DRYING:
Drying temperature
1 10°C to 130°C for ppt. which are formed from organic solvents. Dry for 1 hour.
7. COOLING:
Use desiccators to dry the substance i.e. to absorb the moisture. It contains anhydrous CaCl2 Always keep the desiccators closed.
8. WEIGHING:
Never weigh the hot crucible. Record the weight of the crucible with ppt. in the same rough journal. Again keep the crucible in the oven for 20 minutes. If second weight is les then that should be the weight recorded
9. ERRORS IN GRAVIMETRIC ANALYSIS:
Observe all the precautions explained in steps no. 1 - 8 which will ensure that there are no errors.
GREEN CHEMISTRY
PRINCIPLES:

1. 
   Need of alternative pathways for chemical reaction and usage which doesn't produce waste.
   
2. 
   If waste is formed, it should be non- toxic, pollution free and degradable.
   
3. 
   Synthesize products with maximum effect a per requirement and least harmful to human and environment
   
4. 
   Catalytic reagents are renewable whereas stoichiometric ones are wasteful and polluting
   
5. 
   Reaction vessels should be strong enough to minimize the potential of chemical accident.
   
6. 
   Accidental spillage of hazardous by-product should be prevented by properly monitoring them
   
7. 
   Production Of compounds with multi-functional group should be minimized as it involves use of many reagents and hence generation of more by-products.
   
8. 
   Rate of production should be a according to the availability of feedstock/raw-material for maintenance of ecological balance.
   

PRACTISING GREEN CHEMISTRY IN LAB

1. 
   Use minimum organic solvents (like acetone alcohol) for cleaning, rinsing dissolving etc.
   
2. 
   Avoid them as far as possible in first place itself. Wherever possible water should be used for all above purposes.
   
3. 
   Dry the apparatus in air. (Avoid use of heat for drying and prevent thermal pollution). If required, filter papers can be used.
   
4. 
   As far as possible, dilute solutions should be used instead of solids.
   
5. 
   Minimum amount (as required) of dilute solution should be prepared avoiding wastage.
   
6. 
   All the required arrangement of test (for quantitative analysis) should be done and then burner should used for short required time period only.
   
7. 
   Burner should be kept off as and when possible (match box or gas lighter should always be kept handy)
   
8. 
   Micro-techniques should be followed wherever possible:
   

1. 
   Small test tubes to be used
   
2. 
   Cavity of tile to be used in colour tests not involving heat.
   

iii) Even capillary tubes can be used in various tests.
Section B