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1. Which State of India is the highest producer of cement?
- Uttar Pradesh
- Uttarakhand
- Gujrat
- Madhya Pradesh
Answer and Explanation
Answer: (4) Madhya Pradesh
Explanation:
-> China is largest producer
-> India is second largest producer of cement
-> Madhya Pradesh highest producer state of India (about 23%)
2. Which of the following cement should be kept dry to attain its strength?
- Hydraulic Cements
- Non Hydraulic Cements
- Plaster Cements
- Both (2) and (3)
Answer and Explanation
Answer: (2) Non Hydraulic Cements
Explanation:
-> Hydraulic Cements required hardness materials such as water (common)
-> Non hydraulic cements: doesn’t require any hardeners to attain strength
3. What are the general components of non hydraulic cements, except?
- Lime
- Gypsum
- Silicones
- Oxychloride
Answer and Explanation
Answer: (3) Silicones
Explanation: Basic components of cements are
-> Hydraulic cement: limestone, clay and gypsum
-> Non Hydraulic cement: lime, gypsum plaster, and oxychloride
4. Statement (S1): Lime is also called limestone
Statement (S2): Limestone is called calcium oxide
- Both S1 and S2 are correct
- Both S1 and S2 are not correct
- S1 is correct but S2 is not correct
- S1 is not correct but S2 is correct
Answer and Explanation
Answer: (2) Both S1 and S2 are not correct
Correct Statements:
-> S1: Lime is produced by burning the limestone (naturally occurring) in a kiln. So, both are different
-> S2: Limestone is called calcium carbonate (CaCO3) while lime is called to be quicklime or calcium oxide (CaO)
5. Non hydraulic cements hardens because of carbonation of lime with
- Atmospheric oxygen
- Atmospheric carbon dioxide
- Atmospheric nitrogen
- All of the above
Answer and Explanation
Answer: (2) Atmospheric carbon dioxide
Explanation: Non hydraulic cements take a longer time to harden because of the slow carbonation reaction with carbon dioxide.
6. Hydraulic Cements hardens because of chemical reaction between anhydrous cement powder with
- Oxygen
- Nitrogen
- Dihydrogen monoxide
- Carbon dioxide
Answer and Explanation
Answer: (3) Dihydrogen monoxide
Explanation: The chemical name of water is dihydrogen monoxide.
7. Who is known as the inventor of Portland cement?
- William Portland
- William Wordworth
- William Shatner
- William Aspdin
Answer and Explanation
Answer: (4) William Aspdin
Explanation: Portland cement was patented by William Aspdin in 1824. The name of Portland cement was on Portland stone, Dorset, England.
8. Which is true for general components of cement?
- Highest amount of lime
- Highest amount of Silica
- Lowest amount of lime
- Lowest amount of Alumina
Answer and Explanation
Answer: (2) Highest amount of silica
Explanation: General composition of cement is about:
-> Lime (Calcium oxide): 60 to 65%
-> Silica: 17-25%
-> Alumina: 3-8%
-> Magnesia: 1-3%
-> Sulfur trioxide: ~1%
9. The range of lime (CaO) is within ______ in Portland cement.
- 30 – 35%
- 35 – 55%
- 60 – 65%
- 70 – 75%
Answer and Explanation
Answer: (3) 60 – 65%
10. The main components of Portland cement are:
a. Aluminum oxide b. Calcium oxide c. Magnesium oxide d. Silicon oxide
- a and b are correct
- b and d are correct
- a and d are correct
- b and c are correct
Answer and Explanation
Answer: (2) b and d are correct
Explanation: Four main components of portland cement are:
-> Tricalcium silicate (3CaO · SiO2)
-> Dicalcium silicate (2CaO · SiO2)
-> Tricalcium aluminate (3CaO · Al2O3)
-> Tetra-calcium aluminoferrite (4CaO · Al2O3· Fe2O3)Check our dedicated post to find out the composition of different types of cement.
11. Which of the following are the chemical components of portland cement, except:
- Silicon oxide
- Calcium oxide
- Ferric oxide
- Cuprous oxide
Answer and Explanation
Answer: (4) Cuprous oxide
Explanation: Chemical composition of each compound in portland cement are:-> Silicon oxide (SiO2): ~21%
-> Calcium oxide (CaO): ~ 60%
-> Aluminum oxide (Al2O3): ~7%
-> Ferric Oxide (Fe2O3): 1 to 6%
-> Magnesium oxide (MgO): ~3% (impurity to ferric oxide)
-> Sulfur trioxide: 1 to 2.5%.
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