(SEM I) THEORY EXAMINATION 2023-24 ENGINEERING CHEMISTRY

This document contains the B.Tech First Semester (2023–24) theory examination of Engineering Chemistry (BAS102).
The paper evaluates the student’s understanding of nanotechnology, spectroscopy, electrochemistry, corrosion, polymers, thermochemistry, water treatment, organic chemistry, cement chemistry, and several applied chemical processes relevant to engineering.

The paper is structured into three sections (A, B, and C), testing a range of skills from conceptual knowledge to numerical problem solving and applied chemical reasoning.

SECTION A – Short Answer Questions (Conceptual Understanding)

This section contains 7 questions of 2 marks each, focusing on fundamental chemistry concepts.

Topics include:

1. Nanotechnology

Molecular self-assembly method for nanomaterial preparation

2. Spectroscopy

Beer–Lambert’s law numerical: concentration from transmittance

Effect of polar solvent on π → π* transition (solvatochromism)

3. Electrochemistry

Calculation of EMF of a galvanic cell

Writing the corresponding cell reaction

4. Cement Chemistry

Role of Gypsum in controlling setting time of cement

5. Fuel Chemistry

Gross calorific value (GCV) calculation from coal composition

6. Polymer Science

Concept of polymer blends

This section checks basic recall, conceptual clarity, and analytical application.

SECTION B – Analytical, Structural & Numerical Chemistry (7 marks each, choose any 3)

This section examines deeper understanding of molecular theory, spectroscopy, cement manufacturing, organic synthesis, and water softening.

1. Molecular Orbital Theory

MO diagrams of O₂ and NO

Calculation of bond order

Explanation of magnetic behavior

2. NMR Spectroscopy

Shielding and deshielding effects

Structure determination of organic compound C₃H₇NO from given proton NMR data

3. Cement Manufacturing

Steps in Portland cement manufacturing with labeled diagram

Chemical reactions during setting & hardening

4. Water Softening Methods

Comparison of Zeolite process vs Ion-exchange process (merits, demerits)

5. Grignard Reagent Chemistry

Preparation of Grignard reagent

Reactions of C₂H₅MgBr with aldehydes, ketones, and CO₂

This section tests K2–K3 level: explanation, diagrammatic representation, deduction, and multi-step reasoning.

SECTION C – Long Answer / Derivation / Application-Based Questions

Students must attempt one part from each numbered question (3, 4, 5, 6, 7).
These questions involve detailed descriptions, derivations, diagram drawing, and multi-stage numerical calculations.

Question 3 – Green Chemistry & Liquid Crystals

3(a) Green Chemistry

Any five principles of Green Chemistry

Green synthesis method for Paracetamol

3(b) Liquid Crystals

Classification based on temperature (thermotropic vs lyotropic)

Applications in displays, sensors, optical devices

Question 4 – Stereochemistry & Spectroscopy

4(a) Optical vs Geometrical Isomerism in Cumulative Double Bonds

Even-number cumulenes → optical isomerism

Odd-number cumulenes → cis–trans isomerism

Explanation with structural reasoning

4(b) Short Notes (any two)

UV shifts (bathochromic, hypsochromic effects)

Applications of IR spectroscopy

Molecular vibrations

Question 5 – Electrochemistry & Corrosion

5(a) Lead-Acid Storage Battery

Working principle, diagram

Charging and discharging reactions

5(b) Wet Corrosion

Mechanism (electrochemical corrosion)

Prevention by metallic coatings and corrosion inhibitors

Question 6 – Thermochemistry & Water Treatment

6(a) Bomb Calorimeter

Working with neat diagram

Numerical calculation of GCV & NCV of coal using given data

6(b) Lime-Soda Process

Principle of lime soda softening

Numerical calculation for amount of lime and soda required (considering purity)

Question 7 – Polymers

7(a) Conducting Polymers

Classification (intrinsically conducting, extrinsically conducting)

Applications: batteries, sensors, LEDs, EMI shielding

7(b) Preparation, properties & applications of 3 polymers (any three)

Examples:

Buna-S

Nylon-6,6

(More options continue in original paper)

 Overall Coverage of the Question Paper

This paper thoroughly evaluates engineering-related chemistry knowledge in:

Nanomaterials & quantum effects

Molecular spectroscopy (UV, IR, NMR)

Organic reaction mechanisms (Grignard, cumulenes)

Industrial chemistry (cement, polymers, batteries)

Electrochemistry & thermochemistry

Water softening and corrosion control

Green chemistry & environmental-friendly methods

It integrates theoretical chemistry, industrial applications, and engineering problem-solving, ensuring students build a strong chemical foundation for advanced courses.