- Lead carbonate which is used as a pigment....
“Chemistry Experiments” is a guide for students and teachers who look for various experiments in chemistry. I will be mainly focusing on chemical, fertilizers, water, effluent, latex, dry rubber testing in my latest blog. I hope these experiments will definitely help students & teachers. Please mail me if you all need any further assistance or help in any of these tests.
Tuesday, April 27, 2010
Friday, April 23, 2010
Phenol route is widely used for the production of paracetamol why?
- Simple process, easy or less hazardous
- No pressure reactor required
- No addition of metallic impurity like iron
- Cheap
- Better quality product
- Paracetamol obtained by phenol route are of good quality & purely white crystals.
What are the important things to be noted while conducting the production of paracetamol from phenol?
- Isolation of sections & thorough cleaning & isolation of p-amino phenol is very important.
- Exposure to long timings & duration decomposes the product, especially p-amino phenol.
- Provision of a generator is essential due to critical nature of reaction & also no time can be lost to power breakdown etc.
Identification Test (4) For Paracetamol
- Dissolve 0.2gm paracetamol in 4ml pyridine.
- Add 0.5gm of 4 nitrobenzoyl chloride, boil for 2 or 3 minutes,cool & pour into 40ml water & stirr.
- The ppt after washing with 30ml water, 30ml of 1% W/V solution of sodium carbonate & 30ml water & recrystallisation from alcohol, melts at 210 degree.
Identification Test (3) For Paracetamol
- Boil 0.1gm paracetamol with 1ml HCl for 3 minutes.
- Add 10ml water & cool, no ppt produced.
- Add 0.05ml of 0.1N potassium dichromate, a violet colour slowly develops, which donot become red.( distinction from phenacetin).
Identification Test (2) For Paracetamol
- Dissolve 50mg paracetamol in 100ml methyl alcohol .
- Mix 1ml of the solution with 1ml 0.1N HCl & sufficient methyl alcohol to produce 100ml, extinction of 1cm layer of resulting solution at maximum of 249nm about 0.44
Identification Test (1) For Paracetamol
- Dissolve 0.1gm paracetamol in 10ml water .
- Add 0.05ml ferric chloride solution.
- A violet blue colour is produced.
According to IPS, give the solubility of paracetamol
- Sparingly soluble in water, freely soluble in alcohol, soluble in acetone & in solution of alkali hydroxide.
According to IPS, give a description about paracetamol?
- White crystals or white crystalline powder, odourless, taste -slightly bitter.
According to Indian Pharmaceutical Specifications,what is the dose of paracetamol?
- 0.5 to 1gm, up to 4gm daily, in divided doses.
What is the use of antipyretics?
- In the case of fever antipyretics lower body temperature often as a result of inducing perspiration.
Monday, April 5, 2010
Which type of the process is usually done in the lab for determining VFA test?
- Microsale total recovery steam distillation
What is the function of non volatile fatty acid?
- To increase the stability by virtue of their surface activity.
What is the function of volatile fattyacid?
- To reduce the stability of latex by increasing the ionic strength of the serum.
What is the purpose of adding HCHO to natural rubber latex?
- To reduce the ammonia content to a certain level.
Small filter papers are fastened over the ends of the centrifuging tubes in sludge determination.why?
- To prevent excessive evaporation of water & the possible formation of a surface skin.
What are the chief impurities of natural rubber latex?
- Dirt, sand,bark fragments & Magnesium ammonium phosphate
What is the importance of sludge?
- It refers to non polymer impurities which tend to sediment under the influence of gravity.