BT-101 (GS) – Engineering Chemistry

Write short note on

i) Sludge and Scale

ii) Caustic Embrittlement

iii) Boiler Corrosion

100 ml water sample required 20 ml of N/50 H2SO4 for neutralisation to Phenolphthalein end point. After Methyl Orange was added to this and further acid required was 2.5 ml. Calculate the alkalinity type and extent in terms of CaCO3 equivalent.

An oil sample under test has a Saybolt Universal Viscosity same as that of Standard Gulf oil (low viscosity standard) and Pennsylvanian oil (high viscosity standard) at 210°F. Their Saybolt Universal Viscosities at 100°F are 61, 758 and 420 seconds, respectively. Calculate viscosity index of the sample.

Describe ion exchange process used for softening of water with neat diagram. A zeolite softener was 90% exhausted by removing the hardness completely when 10,000L of hard water sample passed through it. The exhausted zeolite bed required 200L of 3% NaCl solution for its complete regeneration. Calculate the hardness of water sample.

Explain the following properties of the following (any two)

i) Aniline Point

ii) Cloud and Pour Point

iii) Flash and Fire Point

Differentiate chain growth and step growth polymerization. Explain Free radical and Ionic polymerization with the help of suitable example.

Distinguish between thermoplastic and thermosetting resins. Give preparation and application of Urea-Formaldehyde and PVC.

Define and explain the terms involved in the phase rule. Draw a neat labelled phase diagram of water system and explain the areas and curves in it. What is the significance of the triple point and meta stable curve in this system?

What are the important properties that an efficient lubricant should possess? 1.5 gm of a lubricant oil dissolved in alcohol require 2.4 ml of 0.0125 N alcoholic KOH for neutralization. What is neutralization value of the lubricant? If an oil to be used in machinery should not have neutralization value greater than 8.0, is it safe to use the test sample as a lubricant in the machinery?

How can a combination of UV and IR spectroscopy be used to determine the structure of an unknown organic compound? Illustrate with an example.

What is Electronic spectroscopy? An unknown substance absorbs 40% of the light of wavelength 43.5 nm in a cell of 2 cm dimension when has a concentration of 20 gL−1. Under the similar conditions, what percentage of light will be absorbed by a solution containing 40 gL−1 of the same unknown substance?

What is Lime Soda process? Calculate the amount of lime and soda required for softening of 20,000 liters of water whose analysis is: Ca(HCO3)2 = 40.0 ppm; Mg(HCO3)2 = 36.5 ppm; CaSO4 = 34.0 ppm; MgSO4 = 30.0 ppm; CaCl2 = 27.75 ppm.

Write brief note on (Any two)

i) Electro negativity

ii) Polarizability

iii) Oxidation states

Write brief note on (Any two):

i) Electron affinity

ii) Effective Nuclear Charge

iii) Aufbau rule

iv) Atomic and Ionic size