74 + Interview Questions in Admixtures And Construction Chemicals in Concrete Technology Page 1 InterviewSolution

1.	Concrete placed in cold weather will take ____________ time to gain strength.(a) No(b) Less(c) More(d) Equal to hot weatherThis question was addressed to me in a job interview.My question is from Concrete Repair System topic in chapter Admixtures and Construction Chemicals of Concrete Technology
Answer» The correct option is (c) More Easy EXPLANATION: Concrete placed in COLD weather will take LONGER TIME to GAIN strength, delaying form removal and subsequent construction.

Discussion

2.	Dry intervals in surface wetting leads to ___________(a) Cracking(b) Fogging(c) High strength(d) Good workabilityThe question was posed to me in class test.The origin of the question is Concrete Repair System topic in chapter Admixtures and Construction Chemicals of Concrete Technology
Answer» CORRECT choice is (a) CRACKING The explanation is: Dry intervals or PATCHES can lead to crazing or cracking on the slab surface.

Discussion

3.	In a dry environment, concrete strength will be loosed as much as ___________ % in moist environment.(a) 30(b) 40(c) 50(d) 60I got this question in an interview for internship.The origin of the question is Concrete Repair System in chapter Admixtures and Construction Chemicals of Concrete Technology
Answer» The correct option is (c) 50 Explanation: LABORATORY tests show that concrete strength will be loosed as MUCH as 50% in dry environment as compared to moist environment.

Discussion

4.	NaOH is the example of retenders.(a) True(b) FalseI got this question in an interview.This interesting question is from Accelerators and Retarders in division Admixtures and Construction Chemicals of Concrete Technology
Answer»

Discussion

5.	What is the limitation of Carboxylic acids in High range water reducers?(a) 0(b) .1%(c) .2%(d) .3%This question was addressed to me in final exam.This intriguing question originated from Plasticizers in chapter Admixtures and Construction Chemicals of Concrete Technology
Answer» CORRECT choice is (B) .1% Easy explanation: It is the standard value of limitation of Carboxylic acids in HIGH range water reducers i.e. 0.1 percentage.

Discussion

6.	What is water proofing admixtures?(a) Water repellent materials(b) Water fair material(c) Water absorption material(d) Water adsorption materialThe question was posed to me in a national level competition.I'd like to ask this question from Water Proofing Admixtures in section Admixtures and Construction Chemicals of Concrete Technology
Answer» The CORRECT answer is (a) Water repellent materials The best explanation: Water proofing ADMIXTURES are available in powder, PASTE or liquid FORM and MAY consist of pore filling or water repellent materials.

Discussion

7.	Chemically active pore fillers __________ the setting of concrete.(a) Retards(b) Decrease(c) Accelerates(d) No changeThis question was posed to me in an interview for job.The question is from Water Proofing Admixtures in division Admixtures and Construction Chemicals of Concrete Technology
Answer» RIGHT ANSWER is (c) Accelerates To explain I would say: Chemically active pore fillers ACCELERATE the SETTING of concrete and thus render the concrete more impervious at early age.

Discussion

8.	Super plasticizers reduce water requirement by ___________ %.(a) 12-30(b) 10-15(c) 30-42(d) 48I have been asked this question in an international level competition.My question is from Admixtures in section Admixtures and Construction Chemicals of Concrete Technology
Answer» Correct CHOICE is (a) 12-30 The best explanation: Super plasticizers reduce water requirement by 12-30 %. Makes MIX HIGHLY fluid and can be placed with little or no VIBRATION or compaction.

Discussion

9.	Chemically inactive pore fillers ____________ the workability.(a) Decrease(b) Increase(c) Don’t affect(d) ImproveI got this question in a job interview.Enquiry is from Concrete Repair System in chapter Admixtures and Construction Chemicals of Concrete Technology
Answer» The correct option is (d) Improve Best explanation: Chemically inactive PORE FILLERS improve the workability and to FACILITATE the reduction of WATER for given workability and to make DENSE concrete which is basically impervious.

Discussion

10.	Which one is not chemical admixtures?(a) Accelerators(b) Retarders(c) Water-reducing agents(d) Silica fumeI got this question in an interview for internship.I'm obligated to ask this question of Agents in chapter Admixtures and Construction Chemicals of Concrete Technology
Answer» Correct answer is (d) Silica fume To explain I would SAY: ACCELERATORS, retarders, water reducing agents are the chemical admixtures and silica fumes is MINERAL admixtures.

Discussion

11.	Which of the following statement is incorrect about the function of admixtures?(a) To accelerate the initial set of concrete, to speed up the rate of development of strength at early ages(b) To enhance the workability(c) To reduce the segregation in grout and concrete mixers(d) To retard the initial set, to keep concrete workable for a shorter time for placementThis question was posed to me in an online interview.Query is from Admixtures in section Admixtures and Construction Chemicals of Concrete Technology
Answer» Correct option is (d) To retard the INITIAL set, to keep CONCRETE workable for a shorter time for placement To EXPLAIN I would SAY: To retard the initial set, to keep concrete workable for a longer time for placement is incorrect in the above STATEMENT.

Discussion

12.	Air entrainment in concrete increases ___________(a) Strength(b) Workability(c) The effect of temp variations(d) The unit weightThis question was addressed to me in a job interview.Query is from Agents topic in division Admixtures and Construction Chemicals of Concrete Technology
Answer» The CORRECT choice is (b) Workability The BEST explanation: There are the FOLLOWING types of Air entrainment in CONCRETE which helps to INCREASE the workability.

Discussion

13.	What is the content of unburnt fuel in fly ash?(a) 30-60%(b) 15-30%(c) Up to 30%(d) 1-7%I have been asked this question by my school principal while I was bunking the class.My doubt stems from Agents in section Admixtures and Construction Chemicals of Concrete Technology
Answer» The correct option is (c) Up to 30% To explain I would say: The CONTENT of unburnt fuel in FLY ASH has been TESTED according to procedures specified in IS: 1727-1967.

Discussion

14.	Is it possible to use w/c ratio as low as 5?(a) Yes(b) NoThe question was asked in semester exam.My doubt stems from Plasticizers topic in chapter Admixtures and Construction Chemicals of Concrete Technology
Answer»

Discussion

15.	Damp proofing ____________ resist water well enough.(a) Does(b) Does not(c) Doesn’t effect(d) Depends on the temperatureThis question was posed to me at a job interview.This interesting question is from Concrete Repair System topic in chapter Admixtures and Construction Chemicals of Concrete Technology
Answer» The CORRECT CHOICE is (b) Does not The explanation: Damp proofing does not resist water WELL enough to prevent oversaturation from ground water, or excessive and CONSTANT humidity.

Discussion

16.	Water repelling materials like soda, potash soaps, etc make the concrete pervious.(a) True(b) FalseI had been asked this question by my school principal while I was bunking the class.The above asked question is from Water Proofing Admixtures topic in section Admixtures and Construction Chemicals of Concrete Technology
Answer»

Discussion

17.	Chemically active pore fillers __________ the setting of concrete.(a) Retards(b) Decrease(c) Accelerates(d) No changeThis question was addressed to me in an internship interview.This intriguing question originated from Water Proofing Admixtures topic in section Admixtures and Construction Chemicals of Concrete Technology
Answer»

Discussion

18.	The addition of the admixture to the mix __________ the surface tension.(a) Lowers(b) Higher(c) Don’t affect(d) No changeThe question was asked during an internship interview.My doubt is from Damp Proofing Admixtures in chapter Admixtures and Construction Chemicals of Concrete Technology
Answer» The correct choice is (a) LOWERS Easiest explanation: The ADDITION of the ADMIXTURE to the mix lowers the surface tension of the water thereby assisting in the FORMATION of BUBBLES.

Discussion

19.	Classification of admixtures are classified into ________ types.(a) 1(b) 2(c) 3(d) 5The question was posed to me during an online interview.This question is from Admixtures topic in chapter Admixtures and Construction Chemicals of Concrete Technology
Answer» The CORRECT choice is (b) 2 The best EXPLANATION: Classification of admixtures are classified into 2 types i.e. chemical admixtures and MINERAL admixtures.

Discussion

20.	Damp proofing __________ resist water well enough.(a) Does(b) Does not(c) Doesn’t effect(d) Depends on the temperatureI got this question in an international level competition.Asked question is from Damp Proofing Admixtures topic in portion Admixtures and Construction Chemicals of Concrete Technology
Answer» The correct choice is (B) Does not Easy explanation: Damp proofing does not resist WATER well ENOUGH to prevent oversaturation from GROUND water, or excessive and constant humidity.

Discussion

21.	Damp proofing is done with a __________ based mixture.(a) Sand(b) Tar(c) Rubber(d) LeadI have been asked this question in class test.The origin of the question is Damp Proofing Admixtures topic in portion Admixtures and Construction Chemicals of Concrete Technology
Answer» The correct answer is (b) Tar Easiest explanation: Damp proofing is done with a tar based mixture, designed to help discourage water from ADHERING to, or PENETRATING, the MATERIAL’s SURFACE.

Discussion

22.	Chemically inactive pore fillers __________ the workability.(a) Decrease(b) Increase(c) Don’t affect(d) ImproveThis question was posed to me in unit test.The question is from Water Proofing Admixtures topic in section Admixtures and Construction Chemicals of Concrete Technology
Answer» Right choice is (d) Improve Explanation: Chemically inactive pore fillers improve the WORKABILITY and to facilitate the REDUCTION of water for given workability and to make dense CONCRETE which is basically IMPERVIOUS.

Discussion

23.	Entrapped air normally exists in the form of relatively __________ air voids.(a) Small(b) Absent(c) Large(d) MediumThis question was posed to me in an internship interview.This key question is from Water Proofing Admixtures in section Admixtures and Construction Chemicals of Concrete Technology
Answer» Correct choice is (c) Large To EXPLAIN: ENTRAPPED AIR NORMALLY exists in the form of relatively large air voids, which are not DISPERSED uniformly throughout the mix, entrained air exists in the form of minute disconnected bubbles well distributed throughout the mix.

Discussion

24.	What is accelerator?(a) Which speed up the initial set of concrete(b) Which delays the initial set of concrete(c) Which speed up the final set of concrete(d) Which delays the final set of concreteThe question was asked by my college director while I was bunking the class.My doubt stems from Accelerators and Retarders topic in portion Admixtures and Construction Chemicals of Concrete Technology
Answer» Correct option is (a) Which speed up the INITIAL SET of CONCRETE Explanation: An admixture used to speed up the initial set of concrete is called ACCELERATOR.

Discussion

25.	What is super plasticizers?(a) Which adds water for workability(b) Which reduces high range of water for workability(c) Which decreases workability at the same water content(d) Which oxidizes water for workabilityI got this question in an international level competition.The doubt is from Plasticizers topic in division Admixtures and Construction Chemicals of Concrete Technology
Answer» The correct option is (b) Which reduces high RANGE of water for WORKABILITY Best explanation: The ORGANIC substances or combinations of organic and INORGANIC substances, which allow a high reduction in water content for the GIVEN workability at the same water content.

Discussion

26.	What are plasticizers?(a) Which adds water for workability(b) Which reduces water for workability(c) Which decreases workability at the same water content(d) Which oxidizes water for workabilityI had been asked this question in an internship interview.Asked question is from Plasticizers in division Admixtures and Construction Chemicals of Concrete Technology
Answer» RIGHT ANSWER is (B) Which reduces water for workability Easy explanation: The ORGANIC substances or combinations of organic and inorganic substances, which allow a reduction in water content for the given workability, or give higher workability at the same water content.

Discussion

27.	Spherical particles in silica fume has diameter of _______(a) &LT;1 μm(b) &GT;1 μm(c) 1 μm(d) .1 μmI have been asked this question in an interview for job.My question comes from Silica Fume topic in chapter Admixtures and Construction Chemicals of Concrete Technology
Answer» The correct OPTION is (a) &LT;1 μm To explain I would SAY: Silica FUME is an ultrafine material with spherical particles less than 1 μm in diameter, the average being about 0.15 μm.

Discussion

28.	Silica fume is usually added during ____________(a) Before concrete production at a concrete plant(b) After concrete production at a concrete plant(c) Concrete production at a concrete plant(d) CuringI got this question during an interview.Question is from Silica Fume in section Admixtures and Construction Chemicals of Concrete Technology
Answer» CORRECT answer is (c) Concrete PRODUCTION at a concrete PLANT Best EXPLANATION: Silica fume for use in concrete is AVAILABLE in wet or dry forms. It is usually added during concrete production at a concrete plant.

Discussion

29.	Chemically active pore fillers ____________ the setting of concrete.(a) Retards(b) Decrease(c) Accelerates(d) No changeThis question was posed to me in my homework.Asked question is from Concrete Repair System in division Admixtures and Construction Chemicals of Concrete Technology
Answer»

Discussion

30.	Bulk density of the silica fume varies from ____________(a) 130-600 kg/m^3(b) 650 kg/mm^3(c) 75-150 kg/mm^3(d) 750 kg/mm^3I have been asked this question in an interview for internship.My doubt is from Silica Fume topic in division Admixtures and Construction Chemicals of Concrete Technology
Answer» CORRECT answer is (a) 130-600 kg/m^3 To elaborate: The bulk density of silica fume DEPENDS on the degree of DENSIFICATION in the silo and VARIES from 130 (undensified) to 600 kg/m^3.

Discussion

31.	Which one is an anionic surfactants?(a) Polyglycol esters(b) Hydroxylated carboxylic acids(c) Lignosulphonates(d) CarbohydratesI got this question in unit test.My doubt is from Plasticizers topic in division Admixtures and Construction Chemicals of Concrete Technology
Answer» The CORRECT OPTION is (c) Lignosulphonates To elaborate: ANIONIC surfactants such as lignosulphonates and their modifications and DERIVATIVES, SALTS of sulphonates hydrocarbons.

Discussion

32.	Which one is not a chemically active pore filling material?(a) Silicate of soda(b) Aluminium(c) Chalk(d) ZincThe question was asked by my college professor while I was bunking the class.My query is from Water Proofing Admixtures topic in portion Admixtures and Construction Chemicals of Concrete Technology
Answer» The correct ANSWER is (c) Chalk To elaborate: Chemically ACTIVE pore filling materials: silicate of soda, aluminium, ZINC sulphates and CALCIUM chloride.

Discussion

33.	What is Silica Fume?(a) Silica fume is a byproduct of producing silicon metal or ferrosilicon alloys(b) Silica fume is a mono product of producing silicon metal or ferrosilicon alloys(c) Most commonly found in nature as quartz and in various living organisms(d) Hydrocarbon combustion affords the two principal carbon oxides: carbon monoxide and carbon dioxideI got this question in an international level competition.This question is from Silica Fume topic in portion Admixtures and Construction Chemicals of Concrete Technology
Answer» CORRECT choice is (a) SILICA FUME is a BYPRODUCT of producing silicon metal or ferrosilicon alloys Explanation: Silica fume is a byproduct of producing silicon metal or ferrosilicon alloys.

Discussion

34.	Setting time of cement increases by adding ____________(a) Gypsum(b) CaCl2(c) NaOH(d) Hydrogen peroxideI got this question in unit test.This key question is from Accelerators and Retarders in division Admixtures and Construction Chemicals of Concrete Technology
Answer» The CORRECT option is (a) Gypsum The best I can explain: Gypsum is often added to cement and CONCRETE to slow down the drying time. Cement dries quickly. If not added, the cement will SET immediately after MIXING of water LEAVING no time for concrete placing.

Discussion

35.	The specific surface (m^2/kg) of silica fume.(a) 370(b) 15000-30000(c) 45000(d) 420This question was addressed to me in a national level competition.This interesting question is from Silica Fume topic in section Admixtures and Construction Chemicals of Concrete Technology
Answer» Right answer is (b) 15000-30000 Explanation: The specific surface area of SILICA fume can be measured with the BET METHOD or nitrogen ADSORPTION method. It TYPICALLY ranges from 15,000 to 30,000 m^2/kg.

Discussion

36.	Retarders are used to ___________(a) Offset the accelerating effect of cold weather on the setting of concrete(b) Offset the accelerating effect of hot weather on the setting of concrete(c) Offset the Retarding effect of cold weather on the setting of concrete(d) Offset the Retarding effect of hot weather on the setting of concreteI have been asked this question in homework.My question is based upon Accelerators and Retarders in chapter Admixtures and Construction Chemicals of Concrete Technology
Answer» The CORRECT choice is (b) OFFSET the accelerating effect of HOT WEATHER on the SETTING of concrete The best I can explain: Retarders are used to offset the accelerating effect of hot weather on the setting of concrete.

Discussion

37.	Zinc is the example of retenders.(a) True(b) FalseThe question was asked by my school principal while I was bunking the class.My question comes from Accelerators and Retarders in section Admixtures and Construction Chemicals of Concrete Technology
Answer» The correct choice is (a) True Explanation: ZINC delays the initial RATE of hydration of cement and ALSO delays the initial set of CONCRETE.

Discussion

38.	Which one is not a chemically inactive pore filling material?(a) Aluminium(b) Chalk(c) Talc(d) Fullers earthThis question was posed to me in class test.This intriguing question comes from Water Proofing Admixtures in division Admixtures and Construction Chemicals of Concrete Technology
Answer» Correct OPTION is (a) Aluminium To explain: CHEMICALLY inactive filling material: CHALK, FULLERS earth and talc. And aluminium is ACTIVE filling material.

Discussion

39.	Air entrainment in concrete increases ____________(a) Strength(b) Workability(c) The effect of temp variations(d) The unit weightThe question was posed to me in an online quiz.My query is from Concrete Repair System in portion Admixtures and Construction Chemicals of Concrete Technology
Answer» The correct answer is (b) Workability Easiest EXPLANATION: There are FOLLOWING types of Air entrainment in CONCRETE which HELPS to increase the workability.

Discussion

40.	Find the odd one out.(a) Clay and shales(b) Opalinccherts(c) Diatomaceous earth(d) SurkhiI got this question in my homework.My doubt is from Agents in division Admixtures and Construction Chemicals of Concrete Technology
Answer» RIGHT OPTION is (d) Surkhi To EXPLAIN: Clay and shales, opalinccherts, diatomaceous EARTH are natural pozzolnanas and surkhi is artificial one.

Discussion

41.	What do you mean by admixtures?(a) Ingredients which are added to in cement before or after concrete mix(b) Ingredients which are added to make aggregates healthier(c) Ingredients added in cement to make it shinier(d) Ingredients added in concrete to make good workabilityThis question was addressed to me in unit test.This question is from Admixtures topic in chapter Admixtures and Construction Chemicals of Concrete Technology
Answer» The CORRECT answer is (a) Ingredients which are added to in cement before or after concrete mix The explanation is: Admixtures are those ingredients in concrete other than Portland cement, WATER, and AGGREGATES that are added to the mixture IMMEDIATELY before or after the concrete mix.

Discussion

42.	After finishing concrete surface must be kept ___________(a) Dry(b) First dry it and then wet it(c) First wet it and then dry it(d) WetI have been asked this question during an interview for a job.This key question is from Concrete Repair System in division Admixtures and Construction Chemicals of Concrete Technology
Answer» Correct answer is (d) Wet To elaborate: After FINISHING CONCRETE surface must be kept wet, so that it’d be PREVENTED from EVAPORATION.

Discussion

43.	Minute spherical bubbles of size ranging from ______________ microns.(a) 1-100(b) 5-80(c) 15-20(d) 50-60I got this question by my college professor while I was bunking the class.I would like to ask this question from Accelerators and Retarders topic in portion Admixtures and Construction Chemicals of Concrete Technology
Answer» The correct option is (B) 5-80 The BEST I can explain: Minute SPHERICAL bubbles of SIZE ranging from 5-80 microns distributed evenly in the entire MASS of concrete.

Discussion

44.	Find the odd one out.(a) Fly ash(b) Silica Fume(c) Rice husk ash(d) Volcanic tuffsI have been asked this question in an online quiz.This interesting question is from Agents in section Admixtures and Construction Chemicals of Concrete Technology
Answer» Correct answer is (d) Volcanic tuffs To EXPLAIN: Fly ash, silica FUME, rice HUSK ash are ARTIFICIAL pozzolnanas and Volcanic tuffs are the NATURAL one.

Discussion

45.	Damp proofing cracks along with the foundation.(a) True(b) FalseThis question was addressed to me during an interview.My doubt is from Damp Proofing Admixtures in division Admixtures and Construction Chemicals of Concrete Technology
Answer» Correct CHOICE is (a) True To ELABORATE: If the surface has only been damp proofed, the CRACKS and crevices are also present in the COATING of the damp proofing MATERIAL.

Discussion

46.	Which of the following option doesn’t come in chemical admixtures?(a) Plasticizers(b) Pozzolanic(c) Super plasticizer(d) AcceleratorsI have been asked this question during an interview.Question is taken from Admixtures in division Admixtures and Construction Chemicals of Concrete Technology
Answer» Correct option is (B) POZZOLANIC To elaborate: Pozzolanic PROPERTY comes under MINERAL admixtures not under chemical admixtures.

Discussion

47.	What is retender?(a) Which speed up the initial set of concrete(b) Which delays the initial set of concrete(c) Which speed up the final set of concrete(d) Which delays the final set of concreteI have been asked this question in homework.My doubt stems from Accelerators and Retarders topic in division Admixtures and Construction Chemicals of Concrete Technology
Answer» The correct choice is (b) Which delays the initial SET of concrete Easy explanation: An admixture used to DELAY the initial set of concrete is CALLED RETENDER.

Discussion

48.	DPC _________ effective used in concretes that are in contact with water under pressure.(a) Does(b) Doesn’t(c) Doesn’t effect(d) Depends on the temperatureI had been asked this question in my homework.Asked question is from Damp Proofing Admixtures topic in division Admixtures and Construction Chemicals of Concrete Technology
Answer» Right ANSWER is (b) Doesn’t Explanation: Many so-called DAMP proofers are not effective, especially when USED in concretes that are in contact with WATER under pressure.

Discussion

49.	At constant workability, what is the reduction in mixing water?(a) 1-2%(b) 50%(c) .1-.4%(d) 5-15%I got this question in an interview for internship.Enquiry is from Plasticizers topic in section Admixtures and Construction Chemicals of Concrete Technology
Answer» Right answer is (d) 5-15% Explanation: At constant WORKABILITY, the reduction in MIXING WATER is EXPECTED to be of the order of 5% to 15%.

Discussion

50.	Damp proofing __________ the process of water absorption.(a) Increase(b) Slows(c) Doesn’t effect(d) Depends on the mixtureI have been asked this question in quiz.My question is based upon Damp Proofing Admixtures in chapter Admixtures and Construction Chemicals of Concrete Technology
Answer» Correct answer is (b) Slows To EXPLAIN I WOULD say: Damp PROOFING is GOOD for SLOWING down the rate at which moisture is absorbed.

Discussion

Explore topic-wise InterviewSolutions in .

Concrete placed in cold weather will take ____________ time to gain strength.(a) No(b) Less(c) More(d) Equal to hot weatherThis question was addressed to me in a job interview.My question is from Concrete Repair System topic in chapter Admixtures and Construction Chemicals of Concrete Technology

Dry intervals in surface wetting leads to ___________(a) Cracking(b) Fogging(c) High strength(d) Good workabilityThe question was posed to me in class test.The origin of the question is Concrete Repair System topic in chapter Admixtures and Construction Chemicals of Concrete Technology

NaOH is the example of retenders.(a) True(b) FalseI got this question in an interview.This interesting question is from Accelerators and Retarders in division Admixtures and Construction Chemicals of Concrete Technology

What is the limitation of Carboxylic acids in High range water reducers?(a) 0(b) .1%(c) .2%(d) .3%This question was addressed to me in final exam.This intriguing question originated from Plasticizers in chapter Admixtures and Construction Chemicals of Concrete Technology

Chemically active pore fillers __________ the setting of concrete.(a) Retards(b) Decrease(c) Accelerates(d) No changeThis question was posed to me in an interview for job.The question is from Water Proofing Admixtures in division Admixtures and Construction Chemicals of Concrete Technology

Super plasticizers reduce water requirement by ___________ %.(a) 12-30(b) 10-15(c) 30-42(d) 48I have been asked this question in an international level competition.My question is from Admixtures in section Admixtures and Construction Chemicals of Concrete Technology

Chemically inactive pore fillers ____________ the workability.(a) Decrease(b) Increase(c) Don’t affect(d) ImproveI got this question in a job interview.Enquiry is from Concrete Repair System in chapter Admixtures and Construction Chemicals of Concrete Technology

Which one is not chemical admixtures?(a) Accelerators(b) Retarders(c) Water-reducing agents(d) Silica fumeI got this question in an interview for internship.I'm obligated to ask this question of Agents in chapter Admixtures and Construction Chemicals of Concrete Technology

Air entrainment in concrete increases ___________(a) Strength(b) Workability(c) The effect of temp variations(d) The unit weightThis question was addressed to me in a job interview.Query is from Agents topic in division Admixtures and Construction Chemicals of Concrete Technology

What is the content of unburnt fuel in fly ash?(a) 30-60%(b) 15-30%(c) Up to 30%(d) 1-7%I have been asked this question by my school principal while I was bunking the class.My doubt stems from Agents in section Admixtures and Construction Chemicals of Concrete Technology

Is it possible to use w/c ratio as low as 5?(a) Yes(b) NoThe question was asked in semester exam.My doubt stems from Plasticizers topic in chapter Admixtures and Construction Chemicals of Concrete Technology

The addition of the admixture to the mix __________ the surface tension.(a) Lowers(b) Higher(c) Don’t affect(d) No changeThe question was asked during an internship interview.My doubt is from Damp Proofing Admixtures in chapter Admixtures and Construction Chemicals of Concrete Technology

Classification of admixtures are classified into ________ types.(a) 1(b) 2(c) 3(d) 5The question was posed to me during an online interview.This question is from Admixtures topic in chapter Admixtures and Construction Chemicals of Concrete Technology

Damp proofing is done with a __________ based mixture.(a) Sand(b) Tar(c) Rubber(d) LeadI have been asked this question in class test.The origin of the question is Damp Proofing Admixtures topic in portion Admixtures and Construction Chemicals of Concrete Technology

Chemically inactive pore fillers __________ the workability.(a) Decrease(b) Increase(c) Don’t affect(d) ImproveThis question was posed to me in unit test.The question is from Water Proofing Admixtures topic in section Admixtures and Construction Chemicals of Concrete Technology

Entrapped air normally exists in the form of relatively __________ air voids.(a) Small(b) Absent(c) Large(d) MediumThis question was posed to me in an internship interview.This key question is from Water Proofing Admixtures in section Admixtures and Construction Chemicals of Concrete Technology

Spherical particles in silica fume has diameter of _______(a) &LT;1 μm(b) &GT;1 μm(c) 1 μm(d) .1 μmI have been asked this question in an interview for job.My question comes from Silica Fume topic in chapter Admixtures and Construction Chemicals of Concrete Technology

Chemically active pore fillers ____________ the setting of concrete.(a) Retards(b) Decrease(c) Accelerates(d) No changeThis question was posed to me in my homework.Asked question is from Concrete Repair System in division Admixtures and Construction Chemicals of Concrete Technology

Bulk density of the silica fume varies from ____________(a) 130-600 kg/m^3(b) 650 kg/mm^3(c) 75-150 kg/mm^3(d) 750 kg/mm^3I have been asked this question in an interview for internship.My doubt is from Silica Fume topic in division Admixtures and Construction Chemicals of Concrete Technology

Which one is an anionic surfactants?(a) Polyglycol esters(b) Hydroxylated carboxylic acids(c) Lignosulphonates(d) CarbohydratesI got this question in unit test.My doubt is from Plasticizers topic in division Admixtures and Construction Chemicals of Concrete Technology

Setting time of cement increases by adding ____________(a) Gypsum(b) CaCl2(c) NaOH(d) Hydrogen peroxideI got this question in unit test.This key question is from Accelerators and Retarders in division Admixtures and Construction Chemicals of Concrete Technology

The specific surface (m^2/kg) of silica fume.(a) 370(b) 15000-30000(c) 45000(d) 420This question was addressed to me in a national level competition.This interesting question is from Silica Fume topic in section Admixtures and Construction Chemicals of Concrete Technology

Zinc is the example of retenders.(a) True(b) FalseThe question was asked by my school principal while I was bunking the class.My question comes from Accelerators and Retarders in section Admixtures and Construction Chemicals of Concrete Technology

Which one is not a chemically inactive pore filling material?(a) Aluminium(b) Chalk(c) Talc(d) Fullers earthThis question was posed to me in class test.This intriguing question comes from Water Proofing Admixtures in division Admixtures and Construction Chemicals of Concrete Technology

Air entrainment in concrete increases ____________(a) Strength(b) Workability(c) The effect of temp variations(d) The unit weightThe question was posed to me in an online quiz.My query is from Concrete Repair System in portion Admixtures and Construction Chemicals of Concrete Technology

Find the odd one out.(a) Clay and shales(b) Opalinccherts(c) Diatomaceous earth(d) SurkhiI got this question in my homework.My doubt is from Agents in division Admixtures and Construction Chemicals of Concrete Technology

Find the odd one out.(a) Fly ash(b) Silica Fume(c) Rice husk ash(d) Volcanic tuffsI have been asked this question in an online quiz.This interesting question is from Agents in section Admixtures and Construction Chemicals of Concrete Technology

Damp proofing cracks along with the foundation.(a) True(b) FalseThis question was addressed to me during an interview.My doubt is from Damp Proofing Admixtures in division Admixtures and Construction Chemicals of Concrete Technology

Which of the following option doesn’t come in chemical admixtures?(a) Plasticizers(b) Pozzolanic(c) Super plasticizer(d) AcceleratorsI have been asked this question during an interview.Question is taken from Admixtures in division Admixtures and Construction Chemicals of Concrete Technology

At constant workability, what is the reduction in mixing water?(a) 1-2%(b) 50%(c) .1-.4%(d) 5-15%I got this question in an interview for internship.Enquiry is from Plasticizers topic in section Admixtures and Construction Chemicals of Concrete Technology

Damp proofing __________ the process of water absorption.(a) Increase(b) Slows(c) Doesn’t effect(d) Depends on the mixtureI have been asked this question in quiz.My question is based upon Damp Proofing Admixtures in chapter Admixtures and Construction Chemicals of Concrete Technology