Description : Pick up the correct statement from the following: (A) Calcium chloride acts as a retarder (B) Calcium chloride acts as an accelerator (C) Gypsum (calcium sulphate) acts as a retarder (D) Both (b) and (c)
Last Answer : (D) Both (b) and (c)
Description : The most common admixture which is used to accelerate the initial set of concrete is (A) Gypsum (B) Calcium chloride (C) Calcium carbonate (D) None of the above
Last Answer : Answer: Option B
Description : Setting time of cement increases by adding (A) Gypsum (B) Hydrogen peroxide (C) Calcium chloride (D) Sodium oxide
Last Answer : Answer: Option A
Description : Setting time of cement increases by adding (i)gypsum (ii)sodium oxide (iii)calcium chloride [ A ] i [ B ] i and ii [ C ] i and iii [ D ] i, ii and iii
Last Answer : [ A ] i
Description : The most commonly used admixture which prolongs the setting and hardening time is (A) Gypsum (B) Calcium chloride (C) Sodium silicate (D) All of the above
Last Answer : (A) Gypsum
Description : The Most common admixture used to accelerate the initial setting of concrete is a) Gypsum b) Calcium chloride* c) Calcium carbonate d) Calcium bicarbonate
Last Answer : b) Calcium chloride*
Description : The chemical name of "Plaster of Paris" commonly used for setting broken bones is – (1) Calcium nitrate (2) Calcium sulphate (3) Calcium carbonate (4) Calcium chloride
Last Answer : (2) Calcium sulphate Explanation: Plaster of Paris is the common name of Calcium Sulphate hemihydrate, with chemical formula: CaSO4.1/2H2O. Plaster of Paris is produced by heating gypsum to about 150°C.
Description : The chemical name of “Plaster of Paris” commonly used for setting broken bones is (1) Calcium nitrate (2) Calcium sulphate (3) Calcium carbonate (4) Calcium chloride
Last Answer : Calcium sulphate
Description : The basic purpose of a retarder in concrete is (A) To increase the initial setting time of cement paste in concrete (B) To decrease the initial setting time of cement paste in concrete (C) To render the concrete more water tight (D) To improve the workability of concrete mix
Description : To retard the initial setting time of cement, the compound responsible, is (A) Tri-calcium silicate (B) Gypsum (C) Di-calcium silicate (D) Tri-calcium aluminate
Description : Early attainment of strength in rapid hardening cement is mainly due to (A) Gypsum (B) Finer grinding (C) Tri-calcium silicate (D) Tri-calcium aluminate
Description : For reclamation of alkaline soil — is used. a. Lime b. Calcium carbonate c. Gypsum d. None of these
Last Answer : c. Gypsum
Description : Pick up the correct statement from the following: (A) Lime is available in Free State (B) Lime is available by dissolving calcium carbonate in water (C) Lime is available by calcining calcium carbonate at 900°C (D) Lime is nothing but calcium chloride
Last Answer : Answer: Option C
Description : Gypsum is chemically (A) Calcium chloride (B) Potassium sulphate (C) Sodium sulphate (D) Calcium sulphate
Last Answer : (D) Calcium sulphate
Description : Main constituents of Portland cement are calcium aluminate and (A) Gypsum (B) Silicates (C) Sodium silicate (D) Carbonates
Last Answer : (B) Silicates
Description : The maximum quantity of calcium chloride used as an accelerator in cement in percentage by weight of cement is (A) 1 (B) 2 (C) 3 (D) 4
Description : The major calcium salt in bones is (A) Calcium carbonate (B) Calcium chloride (C) Calcium hydroxide (D) Calcium phosphate
Last Answer : Answer : D
Description : A FDA – approved ingredient for protection against painful sensitivity of the teeth due to cold, heat, acids, sweets or contact is (a) Dicalcium phosphate (b) Sodium lauryl sulfate (c) 5% potassium nitrate (d) Zinc chloride (e) Calcium carbonate
Last Answer : Ans: C
Description : Lime water contains (a) sodium hydroxide (b) calcium hydroxide (c) sodium carbonate (d) calcium chloride
Last Answer : Ans:(b)
Description : The chemical that is used to ripen mangoes is - (1) Calcium sulphide (2) Calcium carbide (3) Calcium carbonate (4) Calcium chloride
Last Answer : (2) Calcium carbide Explanation: Calcium carbide is used for artificially ripening fruit. When calcium carbide comes in contact with moisture, it produces acetylene gas, which is quite ... the natural ripening agent ethylene. Acetylene acts like ethylene and accelerates the ripening process.
Description : What is the most common salt in sea water? (1) Calcium carbonate (2) Potassium chloride (3) Sodium chloride (4) Magnesium sulphate
Last Answer : (3) Sodium chloride Explanation: Sodium chloride, also known as salt, common salt, table salt or halite, is an ionic compound with the formula NaCl, representing equal proportions of sodium and ... for the salinity of the ocean and of the extracellular fluid of many multi-cellular organisms.
Description : Write the molecular formulae of: 1. Copper oxide 2. Iron (III) chloride 3. Sodium hydroxide 4. Iron (II) sulphide 5. Lead (II) oxide 6. Hydrogen nitrate (nitric ... Hydrogen sulphate (sulphuric acid) 8. Calcium hydroxide 9. Magnesium carbonate 10.Ammonium carbonate
Last Answer : 1. Copper oxide - CuO 2. Iron (III) chloride - FeCl3 3. Sodium hydroxide - NaOH 4. Iron (II) sulphide - FeS 5. Lead (II) oxide - PbO 6. Hydrogen nitrate (nitric acid) - HNO3 7. ... ) - H2SO4 8. Calcium hydroxide - Ca(OH)2 9. Magnesium carbonate - MgCO3 10.Ammonium carbonate - (NH4)2CO3
Description : Presence of __________ hardness is responsible for the temporary hardness in water. (A) Carbonate (B) Calcium (C) Chloride (D) Sulphate
Last Answer : (B) Calcium
Description : Calcium carbonate is most soluble in: w) 0.2 Molar Sodium carbonate x) 0.1 Molar Calcium chloride y) 0.1 Molar Sodium hydroxide z) 0.1 Molar Hydrochloric acid
Last Answer : ANSWER: Z -- 0.1 MOLAR HYDROCHLORIC ACID
Description : The chemical that is used to ripen mangoes is (1) Calcium sulphide (2) Calcium carbide (3) Calcium carbonate (4) Calcium chloride
Last Answer : Calcium carbide
Description : What is the most common salt in sea water ? (1) Calcium carbonate (2) Potassium chloride (3) Sodium chloride (4) Magnesium sulphate
Last Answer : Sodium chloride
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 : Which of the following waste types are not suitable for co-combustion in cement kilns? a) Chlorine b) Hydrogen c) Calcium d) Carbonate
Last Answer : Chlorine
Description : Hardness of the water is commonly measured in terms of - (1) Calcium carbonate equivalents (2) Calcium sulphate equivalents (3) Magnesium carbonate equivalents (4) Magnesium sulphate equivalents
Last Answer : (1) Calcium carbonate equivalents
Description : Hardness of the water is commonly measured in terms of (1) Calcium carbonate equivalents (2) Calcium sulphate equivalents (3) Magnesium carbonate equivalents (4) Magnesium sulphate equivalents
Last Answer : Calcium carbonate equivalents
Description : Ordinary Portland cement is manufactured from (A) Lime stone and clay (B) Gypsum and lime (C) Pozzolana (D) Lime, pozzolana and clay
Description : Quick setting cement is produced by adding (A) Less amount of gypsum in very fine powdered form (B) More amount of gypsum in very fine powdered form (C) Aluminium sulphate in very fine powdered form (D) Pozzolana in very fine powdered form
Description : Which one of the following is an air binding material? (A) Gypsum (B) Acid-resistant cement (C) Quick lime (D) All of these
Last Answer : Answer: Option D
Description : Rapid hardening cement attains early strength due to (A) Larger proportion of lime grounded finer than normal cement (B) Lesser proportion of lime grounded coarser than normal cement (C) Lesser proportion of lime grounded finer than normal cement (D) Excess percentage of gypsum
Description : The gypsum is added to the cement for (a) Providing high strength to the cement (b) Controlling the initial setting time of cement. (c) Lowering the clinkering temp of cement (d) All the above.
Last Answer : (b) Controlling the initial setting time of cement.
Description : Ammonium sulphate can be produced by reacting gypsum with (A) Ammonia (B) Ammonium carbonate (C) Nitric acid (D) None of these
Last Answer : (B) Ammonium carbonate
Description : Permanent hardness of water is due to the presence of calcium & magnesium (A) Bi-carbonates (B) Sulphates & chlorides (C) Carbonate (D) None of these
Last Answer : (B) Sulphates & chlorides
Description : Alkalinity in water may be caused due to (A) Calcium and magnesium bicarbonates (B) Sodium carbonate (C) Potassium carbonate (D) All the above
Last Answer : (D) All the above
Description : Pick up the correct statement from the following: (A) Deposition of calcium carbonate on the inside of the well pipe, causes incrustation of the pipe (B) Incrustation of the pipe reduces the discharge (C) Acidic waters cause corrosion of the pipes (D) All the above
Description : In a rock calcium carbonate predominates. State whether it is: (A) Siliceous rock (B) Argillaceous rock (C) Calcareous rock (D) None of these
Description : Quick lime is (A) Calcium carbonate (B) Calcium oxide (C) Calcium hydroxide (D) None of the above
Description : A quarter wavelength devices made of crystalline calcite that changes polarization in the optic fiber communication. A. Isolator B. Retarder C. Polarizer D. Filters
Last Answer : B. Retarder
Description : Graphite is used in nuclear reactor as (A) Insulation lining of the reactor (B) Fuel (C) Lubricant (D) Retarder of neutron velocity
Last Answer : (D) Retarder of neutron velocity
Description : A substance which increases the efficiency of a catalyst is termed as: A. Promoter (Answer) B. Activator C. Retarder D. Super catalyst
Last Answer : A. Promoter (Answer)
Description : Which of the following terms refers to a material which slows neutrons? w) retarder x) moderator y) buffer z) bottleneck
Last Answer : ANSWER: X -- MODERATOR
Description : Why is gypsum used in cement ?
Last Answer : Gypsum is used to make cement slowly solidify. When the cement solidifies too fast, the amount of space inside the cement increases , the cement setting becomes weak and brittle. The use of gypsum in cement strengthens the setting of cement. As a result the cement is hard and long lasting.
Description : Which of the following mineral is used in cement industry and plaster of paris? A. Marble B. China Clay C. Gypsum D. Fire Clay
Last Answer : ANSWER: C
Description : Which one of the following is used in large quantities in Cement Industry? (1) Gypsum (2) Limestone (3) Coal (4) Clay
Last Answer : (2) Limestone Explanation: Limestone, as used by the minerals industry, is any rock composed mostly of calcium carbonate (CaCO3). Limestone is used to produce Portland cement, as aggregate ... products, making it a truly versatile commodity. Portland cement is essential to the building industry.
Description : Chemical composition of cement is – (1) Limestone and Clay (2) Limestone, Clay and Gypsum (3) Limestone and Gypsum (4) Clay and Gypsum
Last Answer : (2) Limestone, Clay and Gypsum Explanation: The two important raw materials used for the preparation of cement are : • Limestone : The chemical formula of limestone is CaCO3 and it is used in the manufacture of cement just to provide CaO.