BE Mechanical Engineering छमाही १ (इंजीनियरिंग) - University of Mumbai Question Bank Solutions for Applied Chemistry 1

Write the significance of the following properties of lubricants.
i)Emulsification ii)Cloud point  iii)Fire point

6ml of waste water was refluxed with 25ml ofK₂Cr₂ O₇ solution and after refluxing the excess unreacted dichromate required 20ml of 0. 1 N FAS solution. A blank of distilled water on refluxing with 25 ml of K₂Cr₂O₇ solution required 35ml of 0. 1 N FAS solution . Calculate the COD of the waste water sample.

A 1Oml of sample of water was refluxed with 20ml potassium dichromate solution and after refluxing the excess unreacted dichromate required 26.2ml of 0. 1M FAS solution. A blank 1Oml of distilled water on refluxing with 20ml of dichromate solution required 36ml of 0. 1M FAS solution. Calculate the COD of waste water . 

A 10ml of sample of waste water was refluxed with 20ml of potassium dichromate solution and after refluxing the excess unreacted dichromate required 36.2ml of 0. 1M FAS solution. A blank of 1Om/ of distilled water on refluxing with 20ml of dichromate solution required 46ml of 0. 1M FAS solution. Calculate the COD value of waste water.

6gms of oil was saponified with 50ml of 0.5N alcoholic KOH solution. After refluxing for 2 hours the mixture was titrated with 25ml O.SN HCL Rnd the sponification value of Oil .

Write the preparation, properties and uses of PMMA and Buna-S.

Give the preparation, properties and uses of polymethyl methacrylate polymer.

Give the preparations, properties and uses of Kevlar. 

Write preparation ,properties and uses of following polymers : i) Kevlar ii) Silicone rubber iii) Buna S

Giass transition temperature 

What is glass transition temperature ?Write its significance .

Write a note on Visco-elastic state.

What are the draw backs of natural rubber?

Discuss the drawback of natural rubber.

Natural rubber requires vulcanization .Give reasons .With appropriate reactions explain how the drawbacks are overcome.

Vulcanisation

BUNA-S