Cement Technology Practice Exam 2026 – 190 University-Level
Multiple-Choice Questions with Correct Answers & Detailed
Explanations, Cement Chemistry, Raw Materials, Clinker Production,
Kiln Operations, Grinding, Hydration, Setting Time, Strength Testing,
Quality Control, Durability & Sustainable Cement Manufacturing
SECTION A: Cement Chemistry & Raw Materials
Question 1
Which four principal mineral phases constitute Portland cement clinker?
A. Alite, belite, tricalcium aluminate, tetracalcium aluminoferrite
B. Calcite, quartz, gypsum, hematite
C. Ettringite, monosulfate, portlandite, C-S-H
D. Lime, silica, alumina, iron oxide
Correct Answer: A
Explanation: The four main clinker phases are C₃S (alite), C₂S (belite), C₃A, and C₄AF, each
contributing distinct hydraulic properties.
Question 2
Alite (C₃S) typically comprises approximately what percentage of ordinary Portland cement
clinker?
,A. 5–10%
B. 15–25%
C. 50–70%
D. 80–95%
Correct Answer: C
Explanation: Alite is the dominant phase, providing early strength development; typical
clinker contains 50–70% C₃S by mass.
Question 3
Which clinker phase is primarily responsible for the early-age strength gain of Portland
cement?
A. Belite (C₂S)
B. Alite (C₃S)
C. Tricalcium aluminate (C₃A)
D. Tetracalcium aluminoferrite (C₄AF)
Correct Answer: B
Explanation: Alite hydrates rapidly in the first 28 days, producing C-S-H that drives early
strength development.
Question 4
Belite (C₂S) contributes mainly to which property of hardened cement?
,A. Rapid setting
B. Long-term strength development
C. Sulfate resistance enhancement
D. Color of the cement
Correct Answer: B
Explanation: Belite hydrates slowly, contributing principally to strength gain beyond 28 days
and long-term durability.
Question 5
Tricalcium aluminate (C₃A) is most noted for its role in:
A. Long-term strength
B. Early-age heat evolution and setting behavior
C. Color development
D. Alkali binding
Correct Answer: B
Explanation: C₃A reacts rapidly and exothermically with water and sulfate; it governs setting
behavior and early heat evolution.
Question 6
Gypsum is added to Portland cement clinker primarily to:
, A. Increase strength
B. Retard the rapid hydration of C₃A
C. Improve color
D. Reduce cost
Correct Answer: B
Explanation: Calcium sulfate controls C₃A hydration by forming ettringite, preventing flash
set and regulating workability time.
Question 7
Which raw material primarily supplies calcium oxide in cement manufacture?
A. Clay
B. Limestone
C. Iron ore
D. Sand
Correct Answer: B
Explanation: Limestone (calcium carbonate) is the principal source of CaO, typically
comprising 75–80% of the raw meal.
Question 8
Which raw material supplies silica and alumina in the raw meal?
Multiple-Choice Questions with Correct Answers & Detailed
Explanations, Cement Chemistry, Raw Materials, Clinker Production,
Kiln Operations, Grinding, Hydration, Setting Time, Strength Testing,
Quality Control, Durability & Sustainable Cement Manufacturing
SECTION A: Cement Chemistry & Raw Materials
Question 1
Which four principal mineral phases constitute Portland cement clinker?
A. Alite, belite, tricalcium aluminate, tetracalcium aluminoferrite
B. Calcite, quartz, gypsum, hematite
C. Ettringite, monosulfate, portlandite, C-S-H
D. Lime, silica, alumina, iron oxide
Correct Answer: A
Explanation: The four main clinker phases are C₃S (alite), C₂S (belite), C₃A, and C₄AF, each
contributing distinct hydraulic properties.
Question 2
Alite (C₃S) typically comprises approximately what percentage of ordinary Portland cement
clinker?
,A. 5–10%
B. 15–25%
C. 50–70%
D. 80–95%
Correct Answer: C
Explanation: Alite is the dominant phase, providing early strength development; typical
clinker contains 50–70% C₃S by mass.
Question 3
Which clinker phase is primarily responsible for the early-age strength gain of Portland
cement?
A. Belite (C₂S)
B. Alite (C₃S)
C. Tricalcium aluminate (C₃A)
D. Tetracalcium aluminoferrite (C₄AF)
Correct Answer: B
Explanation: Alite hydrates rapidly in the first 28 days, producing C-S-H that drives early
strength development.
Question 4
Belite (C₂S) contributes mainly to which property of hardened cement?
,A. Rapid setting
B. Long-term strength development
C. Sulfate resistance enhancement
D. Color of the cement
Correct Answer: B
Explanation: Belite hydrates slowly, contributing principally to strength gain beyond 28 days
and long-term durability.
Question 5
Tricalcium aluminate (C₃A) is most noted for its role in:
A. Long-term strength
B. Early-age heat evolution and setting behavior
C. Color development
D. Alkali binding
Correct Answer: B
Explanation: C₃A reacts rapidly and exothermically with water and sulfate; it governs setting
behavior and early heat evolution.
Question 6
Gypsum is added to Portland cement clinker primarily to:
, A. Increase strength
B. Retard the rapid hydration of C₃A
C. Improve color
D. Reduce cost
Correct Answer: B
Explanation: Calcium sulfate controls C₃A hydration by forming ettringite, preventing flash
set and regulating workability time.
Question 7
Which raw material primarily supplies calcium oxide in cement manufacture?
A. Clay
B. Limestone
C. Iron ore
D. Sand
Correct Answer: B
Explanation: Limestone (calcium carbonate) is the principal source of CaO, typically
comprising 75–80% of the raw meal.
Question 8
Which raw material supplies silica and alumina in the raw meal?
