Description : In sewage treatment, its sedimentation is speeded up by commonly adding (A) Hydrochloric acid (B) Lime (C) Copper sulphate (D) Sodium sulphate
Last Answer : (B) Lime
Description : Cooking liquor in case of sulphite process is (A) Sodium sulphite and sodium bisulphite (B) Magnesium sulphite and free SO2 in acid medium (C) Magnesium sulphate and magnesium bicarbonate (D) None of these
Last Answer : (A) Sodium sulphite and sodium bisulphite
Description : Write balanced chemical equations for the following reactions: (a) Dilute sulphuric acid reacts with aluminium powder. (b) Dilute hydrochloric acid reacts with sodium carbonate. (c) Carbon dioxide is passed through lime water. -Chemistry
Last Answer : i hope it helped you
Description : Write balanced chemical equations for the following word equations: (a) Iron + Chlorine → Iron (III) chloride (b) Magnesium + dil sulphuric acid → Magnesium sulphate + water (c) Magnesium + oxygen → ... oxide (d) Calcium oxide + water → Calcium hydroxide (e) Sodium + chlorine → Sodium chloride
Last Answer : (a) Iron + Chlorine → Iron (III) chloride 4Fe + 3Cl2 → 2F2Cl3 (b) Magnesium + dil sulphuric acid → Magnesium sulphate + water 2Mg + 2H2SO4 → 2MgSO4 + 2H2 (c) Magnesium + oxygen → Magnesium oxide 2Mg ... hydroxide CaO + H2O → Ca(OH)2 (e) Sodium + chlorine → Sodium chloride 2Na + Cl2 → 2NaCl
Description : Zeolite used in water softening process (cation exchange) is regenerated by washing with (A) Brine (B) Chloramines (C) Sodium bisulphite (D) Liquid chlorines
Last Answer : (A) Brine
Description : Sodium bisulphite is used for __________ water. (A) Deaeration (B) Dechlorination (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) & (B)
Description : Ethanoic acid is commonly called - (1) Acetic acid (2) Sulphuric acid (3) Sodium Ethoxide (4) Ethyne
Last Answer : (1) Acetic acid Explanation: Ethanoic acid is commonly called acetic acid and belongs to a group of acids called carboxylic acids. 58% solution of acetic acid in water is called vinegar and is used widely as a preservative in pickles.
Description : During sewage treatment, the sewage is subjected to __________ treatment in Imhoff tank. (A) Filtration (B) Digestion (C) Sedimentation (D) Both (B) and (C)
Last Answer : (D) Both (B) and (C)
Description : Out of the following, copper vessels are the most suitable for the storage of (A) Bromine (B) Dry chlorine & dry fluorine (C) Nitric acid (95% and fuming) (D) Phosphoric acid (95%) & sulphuric acid (95% and fuming)
Last Answer : (B) Dry chlorine & dry fluorine
Description : To test chemical oxygen demand (C.O.D.) of sewage, organic matter is oxidised by potassium dichromate in the presence of A. Hydrochloric acid B. Sulphuric acid C. Nitric acid D. Citric acid
Last Answer : ANS: B
Description : The presence of free ammonia in sewage, is detected by A. Boiling B. Adding potassium permanganate C. Adding sulphuric acid D. Phenol-di-sulphuric acid
Last Answer : ANS: A
Description : For detecting the nitrites in the sewage, the matching colour may be developed by adding A. Potassium permanganate B. Sulphuric acid and napthamine C. Phenol-di -sulphuric acid potassium hydroxide D. None of these
Description : For detecting the nitrates in sewage, the colour may be developed by adding A. Potassium permanganate B. Sulphuric acid and napthamine C. Phenol-di -sulphuric acid and potassium hydroxide D. None of these
Last Answer : ANS: C
Description : The substance most commonly used as a food preservative is (a) sodium bicarbonate (b) tartaric acid (c) acetic acid (d) benzoic acid
Last Answer : Ans:(d)
Description : The substance most commonly used as a food preservative is – (1) sodium carbonate (2) tartaric acid (3) acetic acid (4) sodium salt of benzoic acid
Last Answer : (4) sodium salt of benzoic acid Explanation: A preservative is a naturally occurring or synthetically produced substance that is added to products such as foods, pharmaceuticals, paints, biological ... can be antioxidants such as oxygen absorbers, which inhibit the oxidation of food constituents.
Description : The substance most commonly used as a food preservative is (1) sodium carbonate (2) tartaric acid (3) acetic acid (4) sodium salt of benzoic acid
Last Answer : sodium salt of benzoic acid
Description : The function of sedimentation tank in sewage treatment is to: (1) Disinfect the sewage (2) Remove water content (3) Aerate the sewage (4) Remove suspended solids
Last Answer : (4) Remove suspended solids Explanation: The function of sedimentation tank in the sewage treatment is to remove suspended solids.
Description : Before discharging the foul sewage into rivers, it is generally treated by A. Screening B. Sedimentation C. Oxidation D. All the above
Last Answer : ANS: D
Description : For treating the sewage of a large city, you will recommend A. A sedimentation tank and an activated sludge treatment plant B. A plant consisting of Imhoff tanks with low rate trickling filters C. Sedimentation tanks with high rate trickling filters D. None of these
Description : The sewage treatment units in which anaerobic decomposition of organic matter is used, are called A. Imhoff tanks B. Trickling filters C. Sludge sedimentation tanks D. None of these
Description : During sewage treatment, effluent from which one of the following treatment units has minimum wt/vol amount of suspended solids? (a) Detritus channel (b) Primary sedimentation tank (c) Secondary sedimentation tank (d) Activated sludge process aeration tank
Last Answer : (d) Activated sludge process aeration tank
Description : Before discharging the foul sewage into rivers, it is generally treated by (a) screening (b) sedimentation (c) Oxidation (d) sludge digestion and disinfection (e) all the above*
Last Answer : e) all the above*
Last Answer : Remove suspended solids
Description : Salt A commonly used in bakery products on heating gets converted into another salt B which itself is used for removal the hardness of water and a gas C is evolved. The gas C when passed through lime water ,turns it ... © A is baking soda ,B is washing soda and C is carbon dioxide (d) both a and c
Last Answer : (d) both a and c
Description : Most commonly used bleaching agent is – (1) Sodium chloride (2) Alcohol (3) Carbon dioxide (4) Chlorine
Last Answer : (4) Chlorine Explanation: Chlorine is used to disinfect water and is part of the sanitation process for sewage and industrial waste. During the production of paper and cloth, it is used ... in water Bleaching powder is an important and a commonly used bleaching agent prepared from chlorine.
Description : Most commonly used bleaching agent is (1) Sodium chloride (2) Alcohol (3) Carbon dioxide (4) Chlorine
Last Answer : Chlorine
Description : Nitro-glycerine absorbed in wood flour, sodium nitrate or ammonium nitrate is commercially used as controlled explosive called dynamite. The raw material used for its manufacture are glycerine, nitric acid and (A) Sulphuric acid (B) Phosphoric acid (C) Hydrochloric acid (D) Hydrofluoric acid
Last Answer : (A) Sulphuric acid
Description : This substance is sweet-smelling and is used in making perfumes and flavouring agents. It is called- (1) Sodium ethanoate (2) Lime water (3) Hydrogencarbonates (4) Ester
Last Answer : (4) Ester Explanation: The correct answer is Ester. An ester is a sweet-smelling substance, used in making perfumes and flavouring agents.
Description : Which one of the following is commonly used for pulp bleaching in the paper industry? (1) Mild sulphuric acid (2) Glucose isomerase (3) Hydrogen peroxide (4) Iodine and water
Last Answer : (3) Hydrogen peroxide Explanation: Bleaching of wood pulp is the chemical processing carried out to decrease the color of the pulp, so that it becomes whiter. Alkaline hydrogen ... responsible for absorbing visible light. The decomposition of hydrogen peroxide is catalyzed by transition metals.
Last Answer : Hydrogen peroxide
Description : Use of chlorine in the treatment of sewage (A) Helps in grease separation (B) Increases the biological oxygen demand (BOD) (C) Causes bulking of activated sludge (D) Aids in flocculation
Last Answer : (A) Helps in grease separation
Description : Presence of carbonaceous matter in the sewage (A) Causes reduction in its dissolved oxygen content thereby endangering the life of aquatic creatures (B) Reduces sulphate ions to sulphides causing obnoxious ... quantity of chlorine used for its purification (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Potassium meta-bisulphite is used as a food preservative for (1) Squash (2) Tomato Ketchup (3) Fruit Juices (4) Pickles
Last Answer : Fruit Juices
Description : 0.257g of organic substance was heated with conc. sulphuric acid and then distilled with excess of strong alkali .the ammonia gas evolved was absorbed in 50ml of .1M HCl which required 23.2ml of c for neutralization at the end of the process. Determine the % of nitrogen in the compound ?
Last Answer : A. Vol of 0 .1M HCl taken = 50ml Vol of .1MNaOH used for neutralization of unused acid=23.2ml Now, 23.2 ml of .1MNaOH =23.2ml of .1MHCl Vol of .1MHCl unused=23.2ml Vol of .1MHCl required ... NH3 solution contain nitrogen = 14*26.8/10*1000 Percentage of Nitrogen=14*26.8*100/10*1000*.257 =14.6%
Description : A compound X' on heating with excess conc. sulphuric acid at 443 K gives an unsaturated compound Y'. X' also reacts with sodium metal to evolve a colourless gas Z'. Identify X', Y' ... the chemical reaction of formation of Y' and also write the role of sulphuric acid in the reaction. -Science
Last Answer : X-Ethanol/ (C2H5OH)/Ethyl AlcoholY- Ethene / (C2H4)Z- Hydrogen/ (H2)Role of sulphuric acid - dehydrating agent
Description : The acid which fails to liberate carbon dioxide from sodium bicarbonate is : (1) Acetic acid (2) Formic acid (3) Carbonic acid (4) Sulphuric acid
Last Answer : (4) Sulphuric acid Explanation: Sodium bicarbonate and organic acid (Formic acid, Acetic acid, Carbonic acid, etc) react vigorously to liberate carbon dioxide. For example, Sodium bicarbonate (NaHCO3) when treated with acetic acid reacts vigorously to liberate carbon dioxide.
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
Last Answer : Sulphuric acid
Description : Which among the following stage is suitable indicator when solution of sodium carbonate is mixed with sulphuric acid ? (1) Methylene blue (2) Methyl red (3) Phenolphthaline (4) Methyl orange
Last Answer : Methyl orange
Description : What is the most commonly used substance in fluorescent tubes? (1) Sodium oxide and argon (2) Sodium vapour and neon (3) Mercury vapour and argon (4) Mercury oxide and neon
Last Answer : (3) Mercury vapour and argon Explanation: A fluorescent lamp or fluorescent tube is a gas-discharge lamp that uses electricity to excite mercury vapour. it contains mercury vapour and ... A fluorescent lamp converts electrical power into useful light more efficiently than an incandescent lamp.
Last Answer : Mercury vapour and argon
Description : Bleaching powder (chemically known as calcium chloro hypochlorite) is commercially produced by the action of chlorine on (A) Slaked lime (B) Soda lime (C) Calcium perchlorate (D) None of these
Last Answer : (A) Slaked lime
Description : Which two gases are used to disinfect water in sewage treatment facilities? w) helium and nitrogen x) ozone and chlorine y) oxygen and hydrogen z) nitrogen and chlorine
Last Answer : ANSWER: X -- OZONE AND CHLORINE
Description : What is the substance that reacts with hydrochloric acid to produce chlorine gas?
Last Answer : This compound is the manganese dioxide, MnO2.
Description : An ideal plastic substance indicates no deformation, when stressed upto yield stress, but behaves like a Newtonian fluid beyond yield stress. Which of the following is an ideal plastic? (A) Sewage sludge (B) Rubber latex (C) Blood (D) Sugar solution
Last Answer : (A) Sewage sludge
Description : The most commonly used chemical coagulant in water treatment is (A) Ferrous sulphate (B) Alum (C) Lime (D) Hydrazine
Last Answer : (B) Alum
Description : Most widely and commonly used coagulant for the removal of suspended impurities in water is (A) Bleaching powder (B) Slaked lime (C) Alum (D) Copper sulphate
Last Answer : (C) Alum
Description : Chemical name of vinegar is -------? A. Sodium Nitrate B. Dilute acetic acid (Answer) C. Chloride of lime D. Calcium E. None of these
Last Answer : B. Dilute acetic acid (Answer)
Description : Which of the following reactions involve NEITHER oxidation nor reduction? w) burning antimony in chlorine x) decomposition of potassium chlorate y) reaction of sodium with water z) reaction of potassium hydroxide with nitric acid
Last Answer : ANSWER: Z -- REACTION OF POTASSIUM HYDROXIDE WITH NITRIC ACID
Description : Bleaching powder is prepared by passing – (1) Chlorine over slaked lime (2) Oxygen over slaked lime (3) Carbon dioxide over slaked lime (4) Chlorine over quick lirne
Last Answer : (1) Chlorine over slaked lime Explanation: Calcium hypochlorite (bleaching powder) is manufactured by the calcium process: 2Cl2 + 2Ca(OH)2 (slaked lime) Ca(OCl)2 + CaCl2 + 2H2O. Bleaching powder is actually a mixture of calcium hypochlorite and the basic chloride with some slaked lime.