Description : Agglomeration of individual particles into clusters (flocs) is called flocculation. To prevent flocculation, the most commonly used dispersing agents are (A) Carbonates (B) Sulphates (C) Silicates & phosphates (D) Bi-carbonates
Last Answer : (C) Silicates & phosphates
Description : Magnesium and calcium __________ cause temporary hardness of water. (A) Carbonates (B) Bicarbonates (C) Phosphates (D) Sulphates
Last Answer : (B) Bicarbonates
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 : Presence of dissolved impurities of __________ is responsible for the red brownish color of water. (A) Carbonates (B) Bi-carbonates (C) Iron & manganese (D) Arsenic
Last Answer : (C) Iron & manganese
Description : The commonest form of iron & manganese found in ground water as pollutant is in the form of their (A) Carbonates (B) Bi-carbonates (C) Chlorides (D) Sulphides
Last Answer : (B) Bi-carbonates
Description : Injurious effects of sulphates can be replaced with the addition of ________: a. Nitrates b. Phosphates c. Ammonia d. Ca & Mg
Last Answer : Nitrates
Description : The impurity of mixing water which affects the setting time and strength of concrete, is (A) Sodium sulphates (B) Sodium chlorides (C) Sodium carbonates and bicarbonates (D) Calcium bicarbonates
Last Answer : Answer: Option C
Description : Certain carbonates and phosphates are removed by
Last Answer : Certain carbonates and phosphates are removed by A. Skin B. Liver C. Kidneys D. None of the above
Description : $ Minerals such as carbonates and phosphates acts as buffers. ! Biomolecules contain only 25 elements out of the 109 known elements.
Last Answer : $ Minerals such as carbonates and phosphates acts as buffers. ! Biomolecules contain only 25 elements out of ... wrong D. If both As and R are wrong.
Description : Diamond is chemically (a) a mixture of metal carbonates (b) pure carbon (c) a pure form of sand (d) a mixture of calcium and magnesium phosphates
Last Answer : Ans:(b)
Description : Out of the following, the __________ pipe has the least corrosion resistance. (A) Mild steel (B) Copper (C) Cast iron (D) Wrought iron
Last Answer : D) Wrought iron
Description : Aqueous nitric acid is stored in __________ vessel. (A) Plain carbon steel (B) Stainless steel (C) Cast iron (D) Thermosetting plastic material
Last Answer : (C) Cast iron
Description : Which of the following is an yellow pigment? (A) Titanium dioxide (B) Ferrous sulphate (C) Lead chromates (D) Zinc sulphides
Last Answer : (C) Lead chromates
Description : __________ is the process of coating the surface of steel with aluminium oxide, thereby imparting it increased resistance to corrosion & oxidation upto a temperature of 700°C. (A) Veneering (B) Galvanising (C) Electroplating (D) Calorising
Last Answer : (D) Calorising
Description : Builders are added in soap to act as (A) Cleaning power booster (B) Anti-redeposition agent (C) Corrosion inhibitor (D) Fabric brightener
Last Answer : (A) Cleaning power booster
Description : Pipes for bi-cycle frames are made of __________ steel. (A) Hot rolled (B) Chrome carbon (C) Cold rolled (D) Stainless
Last Answer : (C) Cold rolled
Description : Though tin occurs lower than iron in the electrochemical series, yet it is coated on steel for corrosion protection, because of its (A) Lower cost (B) Abundant availability (C) Resistance to vegetable acids as the tin plate are commercially used in 'canning' industry (D) None of these
Last Answer : (C) Resistance to vegetable acids as the tin plate are commercially used in 'canning' industry
Description : Aqueous nitric acid is stored in (A) Steel drum (B) Stainless steel vessel (C) Cast iron vessel lined with acid-proof masonry brick (D) Cast iron vessel
Last Answer : (B) Stainless steel vessel
Description : Lime and soda ash are added to water to remove (A) Bicarbonates & sulphates of calcium and magnesium (B) Undesirable taste and odour (C) Bacteria (D) Its corrosiveness
Last Answer : (A) Bicarbonates & sulphates of calcium and magnesium
Description : Wrought iron is a suitable material of construction for handling __________ solutions (A) Dilute acidic (B) Concentrated acidic (C) Alkalis & alkaline (D) None of these
Last Answer : (C) Alkalis & alkaline
Description : Wrought iron is a suitable material of construction for handling __________ solutions. (A) Dilute acidic (B) Concentrated acidic (C) Alkalis & alkaline (D) None of these
Description : __________ is added in stainless steel to prevent inter crystal corrosion. (A) Vanadium (B) Niobium (C) Chromium (D) Nickel
Last Answer : (B) Niobium
Description : When dilute aqueous solutions of two salts are mixed, the process is associated with (A) Decrease in temperature (B) Increase in temperature (C) No change in temperature (D) Change in temperature which is a function of composition
Last Answer : B) Increase in temperature
Description : Milk fever in cows occurs due to the lack of (a) Phosphates (b) Calcium (c) Iron (d) Iodine
Description : CHOOSE THE MOST APPROPRIATE RESPONSE 41.1 Absorption of oral iron preparations can be facilitated by coadministering: A. Antacids B. Tetracyclines C. Phosphates D. Ascorbic acid
Last Answer : D. Ascorbic acid
Description : Mild steel is (A) A low carbon steel (0.05 to 0.3% carbon) (B) Highly resistant to corrosion (as much as stainless steel) (C) A high carbon steel (0.5 to 1.5% carbon) (D) Very poor in strength & ductility
Last Answer : (A) A low carbon steel (0.05 to 0.3% carbon)
Description : Presence of manganese in alloy steel improves its (A) Corrosion resistance (B) Cutting ability (C) Abrasion resistance & toughness (D) Elasticity & creep resistance
Last Answer : (C) Abrasion resistance & toughness
Description : Pick out the wrong statement about coating/electroplating of metals. (A) Phosphate coating is used as an excellent base for paints & enamels (B) Phosphate coating is less corrosion resistant than ... coating metal is made the anode (D) Calorising is the process of coating steel with chromium
Last Answer : (D) Calorising is the process of coating steel with chromium
Description : Which of the following is an example of stress corrosion? (A) Season cracking of brass (B) Caustic embrittlement of steel (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : Option C
Description : Which of the following is false? (a) Mica is usually found in metamorphic and igneous rocks (b) Aluminium has the advantage over iron as it is resistant to corrosion (c) line is mostly used in galvanising iron and steel goods (d) Manganese is largely used in making fertilizers
Last Answer : Ans: (d)
Description : Consider the following statements: 1. Carbonate hardness is due to bicarbonates. 2. Non-carbonate hardness is due to sulphates and chlorides of Ca and Mg. 3. Both the hardnesses can be removed by lime-soda method. 4. Both the hardnesses can be ... (b) 1, 2 & 4 only (c) 2, 3 & 4 only (d) 1, 2, 3 & 4
Last Answer : (a) 1, 2 & 3 only
Description : Wrought iron is (A) High carbon iron (B) Highly resistance to acid corrosion (C) Malleable & ductile; and hence is used for chain links, hooks & couplings (D) An alloy of iron, chromium & carbon
Last Answer : (C) Malleable & ductile; and hence is used for chain links, hooks & couplings
Description : Corrosion resisting properties of cast iron are significantly improved by the addition of 12 - 15% of (A) Tungsten (B) Vanadium (C) Silicon (D) All (A), (B) & (C)
Last Answer : (C) Silicon
Description : Wrought iron does not have (A) Uniform strength in all directions (B) Ability to hold protective coating (C) High ductility & corrosion resistance (D) Easily weldable characteristics
Last Answer : Option A
Description : Wrought iron is not (A) Ductile & resistant to corrosion/rusting (B) Weldable easily (C) Having uniform strength in all directions (D) Having maximum tensile strength along the lines of slag distribution
Description : (a) Show on a diagram the transfer of electrons between the atoms in the formation of MgO. Write symbols of cation and anion present in MgO. (b) Name the solvent in which ionic compounds are generally soluble. (c) Why are aqueous solutions of ionic compounds able to conduct electricity? -Chemistry
Last Answer : (b) Ionic compounds are soluble in water. (c) It is because aqueous solutions consist of ions which can move freely in them and carry current.
Description : Which of the following alkali metal ions has the lowest ionic mobility in aqueous solutions?
Last Answer : Which of the following alkali metal ions has the lowest ionic mobility in aqueous solutions? A. `Li^(+)` B. `Na^(+)` C. `Rb^(+)` D. `Cs^(+)`
Description : Acidity of diprotic acids in aqueous solutions increases in the order
Last Answer : Acidity of diprotic acids in aqueous solutions increases in the order A. `H_(2)S lt H_(2)Se lt H_(2)Te` B. `H_ ... D. `H_(2)Se lt H_(2) Te ltt H_(2)S`
Description : A compound is made by mixing cobalt (III) nitrite and potassium nitrite solutions in the ratio of 1:3. The aqueous solution of the compound showed 4 p
Last Answer : A compound is made by mixing cobalt (III) nitrite and potassium nitrite solutions in the ratio of 1:3. The aqueous ... )]` D. `K[Co(NO_(2))_(4)]`
Description : Each of these are added to a mixture of aqueous solutions of iodide and `CHCl_(3)` separately. Which will give a positive test for iodine when the sol
Last Answer : Each of these are added to a mixture of aqueous solutions of iodide and `CHCl_(3)` separately. ... . NaBr solution C. Chlorine water D. Bromine water
Description : Beryllium oxide is treated separately with aqueous HCl and aqueous NaOH solutions.
Last Answer : Write balanced chemical equations : Beryllium oxide is treated separately with aqueous HCl and aqueous NaOH solutions.
Description : What statement about Arrhenius acids is FALSETheir aqueous solutions are electrolytesTheir water solutions are called aqueous acids They increase the concentration of hydroxide ions in aqueous solutionThey are molecular compounds with hydrogen ions?
Last Answer : The answer is: They increase the concentration of hydroxide ions in aqueous solution.
Description : Explain the rule to find specific heat of aqueous solutions.
Last Answer : For aqueous solutions of salts, the specific heat can be estimated by assuming the specific heat of the solution equal to that of the water alone. Thus, for a 15% by weight solution of sodium chloride in water, the specific heat would be approximately 0.85.
Description : A student prepares aqueous solutions of the following salts: Copper sulphate, ferrous sulphate, sodium sulphate and barium chloride. Write the color of each solution thus formed?
Last Answer : Answer. Copper sulphate (aq) – blue in color Ferrous sulphate (aq) – pale green in color Sodium sulphate (aq) – colorless Barium chloride (aq) – white in color
Description : Which of the following aqueous solutions would hav the lowest boiling point? Would it be a 1.0 molal solution of: w) Hydrochloric acid x) Sodium Hydroxide y) Acetic Acid, z) Magnesium Chloride
Last Answer : ANSWER: Y -- ACETIC ACID
Description : Amphoteric substances: w) act as either bases or acids x) precipatate from aqueous solutions y) salt out of basic solutions z) form emulsions in oils
Last Answer : ANSWER: W -- ACT AS EITHER BASES OR ACIDS
Description : The theory of interionic attraction attributed to Debye and Hückel: w) was disproved by Arrhenius x) accounts quantitatively for the attraction between ions in dilute aqueous solutions y) does not account for kindered "ion-activity" z) accounts for intra-molecular polar bonds
Last Answer : ANSWER: X -- ACCOUNTS QUANTITATIVELY FOR THE ATTRACTION BETWEEN IONS IN DILUTE AQUEOUS SOLUTIONS
Description : Which of the following is NOT a general property of hydroxide bases in aqueous solution? w) High solubility x) Bitter taste y) Ability to neutralize aqueous acid solutions z) Ability to change phenolphthalein from colorless to red
Last Answer : ANSWER: W -- HIGH SOLUBILITY (The hydroxides of the alkali metals are soluble in water but all the other metal hydroxides are only moderately or sparingly soluble.)
Description : Explain the stability of carbonates & bicarbonates of alkali metals .
Last Answer : The alkali metals form salts with all the oxo-acids. They are generally soluble in water and thermally stable. Their carbonates (M2CO3) and in most cases the hydrogencarbonates (MHCO3) also are highly ... the formation of more stable Li2O and CO2. Its hydrogencarbonate does not exist as a solid.