Basic Civil Engineering Questions and Answers – Ingredients of Cement


This set of Basic Civil Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Ingredients of Cement”.

1. What is the most dominant constituent of cement?
a) Silica
b) Lime
c) Magnesia
d) Alumina
View Answer

Answer: b
Explanation: Cement contains about 60-65% of lime. Silica constitutes 17-25%, alumina 3-8% and magnesia 1-3%.

2. Deficiency of lime in cement leads to:
a) Unsound cement
b) Disintegration of cement
c) Quick setting of cement
d) Expansion of cement
View Answer

Answer: c
Explanation: Presence of lime in sufficient quantity is necessary to form silicates and aluminates of calcium. Excess lime leads to expansion, disintegration and unsoundness of cement.

3. What effect does calcium sulphate have on cement?
a) Retards setting action
b) Acts as flux
c) Imparts colour
d) Reduces strength
View Answer

Answer: a
Explanation: Calcium sulphate is found in cement in the form of gypsum. Its slows down the setting time of cement.


4. Which of the following adds a quick-setting property to cement?
a) Magnesium oxide
b) Silicon dioxide
c) Iron oxide
d) Aluminium oxide
View Answer

Answer: d
Explanation: Aluminium Oxide or Alumina is present in small quantity in cement and it helps in a quick-setting property.

5. Which of the following imparts greenish grey colour to cement?
a) Calcium silicate
b) Calcium aluminate
c) Calcium aluminate ferrite
d) Calcium carbonate
View Answer

Answer: c
Explanation: Calcium silicate and calcium aluminate are pure white minerals. Calcium aluminate ferrite is brown in colour, but due to absorption of light by magnesium, present as an impurity, greenish grey colour is imparted to cement.

6. Excess of Alkali in cement results in:
a) Dry cement paste
b) Efflorescence
c) Less plasticity
d) Unsound cement
View Answer

Answer: b
Explanation: Efflorescence is the formation of powdery substance on the surface of masonry or concrete work. Alkalis usually get carried away by flue gases during heating. In excess quantity, they result in alkali-aggregate reaction.

7. What function does iron oxide perform in cement?
a) Increases strength
b) Makes cement sound
c) Increases setting time
d) Acts as flux
View Answer

Answer: d
Explanation: Iron oxide acts as a flux, in addition to being responsible for imparting colour to cement. If the temperature goes higher, then iron oxide reacts with aluminium and calcium and results in the formation of calcium aluminate ferrite.

8. How many major ingredients are present in the composition of cement?
a) 8
b) 5
c) 10
d) 6
View Answer

Answer: a
Explanation: There are 8 main ingredients present in cement. They are lime, silica, alumina, magnesia, iron oxide, calcium sulphate, sulphur trioxide and alkalis.

9. Sulphur in cement is present in what amount?
a) 0.5 – 6 g
b) 1 – 2.5%
c) 0.5 – 6%
d) 1 – 2.5g
View Answer

Answer: b
Explanation: The presence of ingredients is expressed in percentage. Iron oxide is present in 0.5-6% and sulphur 1-2.5%.

10. An excess of magnesium oxide after 5% is harmful to cement.
a) True
b) False
View Answer

Answer: a
Explanation: Excess of magnesium causes problems in structures built with this cement. It causes cracks in both mortar and concrete after they harden.

Sanfoundry Global Education & Learning Series – Basic Civil Engineering.

To practice all areas of Basic Civil Engineering, here is complete set of 1000+ Multiple Choice Questions and Answers.

Participate in the Sanfoundry Certification contest to get free Certificate of Merit. Join our social networks below and stay updated with latest contests, videos, internships and jobs!

Manish Bhojasia - Founder & CTO at Sanfoundry
Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He is Linux Kernel Developer & SAN Architect and is passionate about competency developments in these areas. He lives in Bangalore and delivers focused training sessions to IT professionals in Linux Kernel, Linux Debugging, Linux Device Drivers, Linux Networking, Linux Storage, Advanced C Programming, SAN Storage Technologies, SCSI Internals & Storage Protocols such as iSCSI & Fiber Channel. Stay connected with him @ LinkedIn | Youtube | Instagram | Facebook | Twitter