Chemical Engineering Archives

Chemical Engineering

Prepare with the best Chemical Engineering MCQs with answers and detailed explanations for exams and job tests. Our collection covers key topics such as chemical process calculations, thermodynamics, fluid mechanics, heat transfer, mass transfer, reaction engineering, instrumentation, and plant design. These Chemical Engineering multiple-choice questions are ideal for students, competitive exam aspirants, and professionals preparing for NTS, PPSC, FPSC, PEC exams, GATE, university entry tests, and job interviews. Practice online with updated Chemical Engineering MCQs to strengthen your concepts and improve technical problem-solving skills.

2441. Catalytic cracking compared to thermal cracking of residue of vacuum distillation of crude oil

gives higher yield of petrol.

lower octane number of petrol.

higher sulphur content in the product.

higher gum forming material in petrol.

✅ The correct answer is option A.

2442. H/C ratio (by weight) for the same number of carbon atoms is the highest in case of

aromatics

paraffins

olefins

naphthenes

✅ The correct answer is option D.

2443. Pick out the correct statement about catalytic polymerisation.

H2SO4 polymerisation process gives gasoline rich in unsaturates.

In H2SO4 polymerisation, H3PO4 is always used with 2% steam to prevent meta & ortho H3PO4 formation, which are inactive.

both (a) and (b)

neither (a) nor (b)

✅ The correct answer is option B.

2444. Smoke point of a test sample of kerosene is found to be 15 mm. On removal of __________ from it, the smoke point rises to 25 mm.

n-paraffins

olefins

aromatics

none of these

✅ The correct answer is option C.

2445. The general formula of naphthenes is

CnH2n + 2

CnH2n-6 (where, n ≥ 6)

CnHn-4

same as that for olefins i.e. CnH2n

✅ The correct answer is option D.

2446. Smoke volatility index is equal to smoke point plus

0.42 x(% distilled at 204°C)

5 mm

0.84 x (% distilled at 204°C)

10 mm. approximately

✅ The correct answer is option A.

2447. The proper arrangement of the petroleum fractions in order of their boiling points is

lubricating oil > diesel > petrol > LPG

lubricating oil > petrol > diesel > LPG

petrol > lubricating oil > diesel > LPG

petrol > diesel > LPG > lubricating oil

✅ The correct answer is option A.

2448. Which of the following fractions of petroleum contains maximum sulphur ?

Diesel

Gasoline

Naphtha

Atmospheric residue

✅ The correct answer is option D.

2449. Main constituent of natural gas is

CH4

C2H2

C2H4

C2H6

✅ The correct answer is option A.

2450. Flash point of an oil is determined by the

Pensky Martens apparatus.

Ramsbottom apparatus.

Saybolt viscometer.

Conradson apparatus.

✅ The correct answer is option A.