Portland cement consists mainly of
(A) CaO & SiO2
(B) SiO2 & Al2O3
(C) CaO & Al2O3
(D) CaO & Fe2O3

1 Answer

Answer :

(A) CaO & SiO2

Related questions

Description : Cement mainly contains (A) CaO, SiO2 , Al2O3 (B) MgO, SiO2 , K2O (C) Al2O3 , MgO, Fe2O3 (D) CaO, MgO, K2O

Last Answer : (A) CaO, SiO2 , Al2O3

Description : Which of the following is the second major component of cement? (A) Al2O3 (B) SiO2 (C) CaO (D) Fe2O3

Last Answer : (B) SiO2

Description : Alumina, silica, lime and iron oxide are the basic raw material for the manufacture of Portland cement. The component of Portland cement which first hardens is (A) 5CaO. 3 Al2O3 (B) 3CaO. Al2O3 (C) 3CaO. SiO2 (D) 2CaO. SiO2

Last Answer : Option A

Description : (3) preventing rapid setting of cement Explanation: Portland cement clinker is a hydraulic material which shall consist of at least two-thirds by mass of calcium silicates, the remainder consisting of ... mixed with water by way of a complex series of chemical reactions still only partly understood.

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Description : The slag which floats on the surface of the molten iron generally contains (A) Lime (CaO) 45% (B) Silica (SiO2) 35% (C) Alumina (Al2O3) 12% and MgO, CaSO4, KMnO2 and FeO 8% (D) All the above

Last Answer : Answer: Option D

Description : The slag which floats on the surface of the molten iron generally contains (A) Lime (CaO) 45% (B) Silica (SiO2) 35% (C) Alumina (Al2O3) 12% and MgO, CaSO4, KMnO2 and FeO 8% (D) All these

Last Answer : Answer: Option D

Description : Which catalyst is used in the manufacture of ethylene oxide by oxidation of ethylene? (A) AgO (B) Al2O3 (C) ZnCl2 (D) Fe2O3

Last Answer : (A) AgO

Description : More than 95% of __________ is present in corundum. (A) SiO2 (B) Al2O3 (C) CaSiO2 (D) MgO

Last Answer : B) Al2O3

Description : Limestone addition in the blast furnace is done to flux __________ present in the raw materials. (A) SiO2 (B) Al2O3 (C) MnO2 (D) P

Last Answer : Limestone addition in the blast furnace is done to flux __________ present in the raw materials. (A) SiO2 (B) Al2O3 (C) MnO2 (D) P

Description : Low grade phosphate rock can be used in electrical furnace, because (A) Of the better CaO/SiO2 balance for slag formation (B) CaO content is less (C) It is cheap (D) It produces low cost product

Last Answer : (A) Of the better CaO/SiO2 balance for slag formation

Description : Which of the following is an acidic constituent of B.F. slag? (A) SiO2 (B) FeO (C) MgO (D) CaO

Last Answer : Option A

Description : The main constituents of glass is (A) SiO2 (B) B2O3 (C) Al2O3 (D) Cr2O3

Last Answer : (A) SiO2

Description : Which raw material is used to impart colour to the glass? a) Al2O3 b) CoO c) CaO d) MgO

Last Answer : b) CoO

Description : Which one of the following is classified as a covalent network solid crystal? w) CaO x) SiO2 y) CO2 z) Pb

Last Answer : ANSWER: B -- SiO2

Description : Identify the correct statement with reference to the extractive metallurgy of aluminium. (A) The electrolyte consists of molten Na3AlF6 with approximately 1 to 8% Al2O3 (B) Approximately 80% of ... is immediately vaporised (D) Anode effect sets in when the cryolite concentration goes below 40%.

Last Answer : (A) The electrolyte consists of molten Na3AlF6 with approximately 1 to 8% Al2O3

Description : Glass is (A) Mainly CaO (B) Subjected to galvanising (C) A super cooled liquid (D) All (A), (B) and (C)

Last Answer : (C) A super cooled liquid

Description : The lunar soil consists primarily of: w) FeTiO2 x) A12O3 y) SiO2 z) H2O

Last Answer : ANSWER: W -- FeTiO2

Description : Concrete mainly consists of (A) Cement (B) Aggregates (C) Water (D) All the above

Last Answer : Answer: Option D

Description : Pick out the wrong statement. (A) High early strength cement are made from materials having high silica to lime ratio (B) The function of gypsum in cement is to enhance its initial ... cements are known as silicate cement (D) Major component of greyish Portland cement is tricalcium silicate

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Description : Main constituents of Portland cement are calcium aluminate and (A) Gypsum (B) Silicates (C) Sodium silicate (D) Carbonates

Last Answer : (B) Silicates

Description : __________ is the major constituent of the Portland cement. (A) Calcium carbonate (B) Calcium oxide (C) Tricalcium silicate (D) Calcium sulphate

Last Answer : (C) Tricalcium silicate

Description : Pick out the wrong statement. (A) Dry process is used for the manufacture of cement, when the raw material is blast furnace slag (B) Portland cement is made employing wet process (C) Gypsum is added to Portland cement to lengthen its setting time (D) None of these

Last Answer : (D) None of these

Description : Formation of ordinary Portland cement?

Last Answer : Ordinary Portland cement is form from materials of limestone or chalk and clay in proportion of 78and 22% respectively. The limestone and the clay are crushed and water is added to form slurry. The ... powder and a range of gypsum is added which generate setting or hardening when water is added.

Description : Who Discovered Portland Cement ?

Last Answer : Joseph Aspadin discovers Portland Cement.

Description : Who discovered ‘Portland cement’?

Last Answer : Joseph Aspdin

Description : (1) Calcium silicate and calcium alurninate Explanation: Portland cement is the most common type of cement in general use around the world because it is a basic ingredient of concrete, mortar, stucco ... limited amount of calcium sulfate (which controls the set time) and up to 5% minor constituents.

Last Answer : Milk is a colloidal system in which: (1) Water is dispersed in fat (2) Fat is dispersed in water (3) Fat and water are dispersed in each other (4) Fat is dissolved

Description : The addition of Gypsum to Portland cement helps in–

Last Answer : Preventing rapid settling of cement

Description : Pick up the correct statement from the following: (A) A soil having pH value more than 7 is an acidic soil (B) A soil having pH value less than 7 is an acidic soil (C) A soil ... more than 7 is an alkaline soil (D) A soil containing chemicals for the manufacture of Portland cement is preferred

Last Answer : Answer: Option B

Description : addition of Gypsum to Portland cement helps in

Last Answer : Preventing rapid settling of cement

Description : Newly constructed pavement with ordinary Portland cement attains its working strength after (A) 7 days (B) 14 days (C) 21 days (D) 28 days

Last Answer : Answer: Option D

Description : In ideal pavement is constructed with (A) Bricks (B) Hard soil (C) Portland cement concrete (D) Tar

Last Answer : Answer: Option C

Description : An ordinary Portland cement when tested for its fineness, should not leave any residue on I.S. sieve No. 9, more than (A) 5 % (B) 10 % (C) 15 % (D) 20 %

Last Answer : (B) 10 %

Description : For an ordinary Portland cement (A) Residual does not exceed 10% when sieved through IS Sieve No. 9 (B) Soundness varies from 5 to 10 mm (C) Initial setting time is not less than 30 minutes (D) Compressive stress after 7 days, is not less than 175 kg/cm2

Last Answer : (C) Initial setting time is not less than 30 minutes

Description : For quality control of Portland cement, the test essentially done is (A) Setting time (B) Tensile strength (C) Consistency (D) All the above

Last Answer : D

Description : Ordinary Portland cement is manufactured from (A) Lime stone and clay (B) Gypsum and lime (C) Pozzolana (D) Lime, pozzolana and clay

Last Answer : Answer: Option B

Description : You are asked to construct a massive dam, the type of cement you will use, is (A) Ordinary Portland cement (B) Rapid hardening cement (C) Low heat cement (D) Blast furnace slag cement

Last Answer : Answer: Option C

Description : As compared to ordinary Portland cement, use of pozzolana cement (A) Reduces workability (B) Increases bleeding (C) Increases shrinkage (D) Increases strength

Last Answer : Answer: Option C

Description : As compared to ordinary Portland cement, high alumina cement has (A) Higher initial setting time but lower final setting time (B) Lower initial setting time but higher final setting time (C) Higher initial and final setting times (D) Lower initial and final setting times

Last Answer : Answer: Option A

Description : The cement whose strength is a little lower than the ordinary cement during the first three months but attains afterwards the same strength, is known as (A) Low-heat Portland cement (B) Rapid hardening Portland cement (C) Portland blast slag cement (D) Portland pozzolana cement

Last Answer : Answer: Option A

Description : For the construction of thin R.C.C. structures, the type of cement to be avoided, is (A) Ordinary Portland cement (B) Rapid hardening cement (C) Low heat cement (D) Blast furnace slag cement

Last Answer : Answer: Option D

Description : For construction of structures in sea water, the cement generally preferred to, is (A) Portland-pozzolana cement (B) Quick setting cement (C) Low heat Portland cement (D) Rapid hardening cement

Last Answer : Answer: Option A

Description : For road pavements, the cement generally used, is (A) Ordinary Portland cement (B) Rapid hardening cement (C) Low heat cement (D) Blast furnace slag cement

Last Answer : Answer: Option B

Description : The compound of Portland cement which reacts immediately with water and also sets first is (A) Tri-calcium silicate (B) Di-calcium silicate (C) Tri-calcium aluminate (D) Tetra calcium alumino ferrite

Last Answer : Answer: Option C

Description : The compound of Portland cement which contributes to the strength after two to three years is (A) Tri-calcium silicate (B) Di-calcium silicate (C) Tri-calcium aluminate (D) Tetra-calcium alumino ferrite

Last Answer : Answer: Option B

Description : Portland pozzolana cement possesses (A) Higher resistance to chemical attack (B) Lower heat of hydration (C) Lower shrinkage on drying (D) All the above

Last Answer : Answer: Option D

Description : Portland cement manufactured from pure white chalk and clay but free from iron-oxide, is known as (A) Quick setting cement (B) Rapid hardening cement (C) White cement (D) Low heat Portland cement

Last Answer : Answer: Option C

Description : The normal consistency of ordinary Portland cement is about (A) 10 % (B) 20 % (C) 30 % (D) 40 %

Last Answer : Answer: Option C

Description : Addition of pozzolana to ordinary Portland cement increases (A) Bleeding (B) Shrinkage (C) Permeability (D) Heat of hydration

Last Answer : Answer: Option B

Description : Which of the following cements is suitable for use in massive concrete structures such as large dams? (A) Ordinary Portland cement (B) Low heat cement (C) Rapid hardening cement (D) Sulphate resisting cement

Last Answer : Answer: Option B

Description : According to IS specifications, the compressive strength of ordinary Portland cement after three days should not be less than (A) 7 MPa (B) 11.5 MPa (C) 16 MPa (D) 21 MPa

Last Answer : Answer: Option C