Hardness of water is caused by
(A) Presence of soap lather
(B) Presence of chlorides and sulphates of sodium and potassium
(C) Presence of bicarbonates, sulphates or chlorides of calcium and magnesium
(D) Turbidity
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 : 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 : 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 : Magnesium and calcium __________ cause temporary hardness of water. (A) Carbonates (B) Bicarbonates (C) Phosphates (D) Sulphates
Last Answer : (B) Bicarbonates
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 : Hardness of water can be removed by boiling if it is due to (A) Calcium bicarbonates (B) Calcium sulphates (C) Calcium chloride (D) Calcium nitrates
Last Answer : (A) Calcium bicarbonates
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 : (3) Detergents give lather even with hard water Explanation: Soaps are made of materials found in nature. Detergents are synthetic a big drawback of washing with soap is that the minerals in water ... ions in hard water to create an insoluble residue that can clog drains and stick to clothing.
Last Answer : What is the objective of the 'Kyoto Protocol'? (1) To abolish child labour (2) To eliminate nuclear weapons (3) To increase ground water levels (4) To reduce greenhouse gases
Description : (3) Detergents give lather even with hard water Explanation: Soaps are made of materials found in nature. Detergents are synthetic. a big drawback of washing with soap is that the minerals in water ... ions in hard water to create an insoluble residue that can clog drains and stick to clothing.
Last Answer : Cement is usually a mixture of – (1) Calcium silicate and calcium alurninate (2) Calcium silicate and calcium ferrate (3) Calcium aluminate and calcium ferrate (4) Lime stone and silicon dioxide
Description : The two metal ions that cause hardness to water are: (1) Calcium, Magnesium (2) Sodium, Calcium (3) Sodium, Potassium (4) Sodium, Magnesium
Last Answer : (1) Calcium, Magnesium Explanation: Calcium and magnesium ion cause hardness of water.
Last Answer : Calcium, Magnesium
Description : A child consumes a toxic dose of fluoride. You will:** A. Induce vomiting B. Give a lot of fluids C. Give a lot of fluids and sodium bicarbonates D. Ask patient not to eat for 45 minutes E. Give milk, calcium tablets or magnesium tablets
Last Answer : E. Give milk, calcium tablets or magnesium tablets
Description : Which method will be employed to test the hardness of water? (1) Boiling (2) Distillation (3) Formation of lather with soap (4) None of these
Last Answer : (3) Formation of lather with soap Explanation: Soap solution is used to measure the hardness of rain water, temporarily hard water and sea-water. Hard water does not form soap lather. This is ... in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
Last Answer : Formation of lather with soap
Description : Hard water contains (A) Calcium (B) Magnesium bicarbonates (C) Magnesium sulphate (D) All the above
Description : The presence of which of the following salts in water causes corrosion in steam boilers? (1) Sodium Chloride (2) Magnesium Chloride (3) Calcium bicarbonate (4) Potassium bicarbonate
Last Answer : (2) Magnesium Chloride Explanation: Magnesium chloride is the name for the chemical compound with the formula MgCl2 and its various hydrates MgCl2(H2O)x. These salts are typical ionic halides, being highly soluble in water.
Description : The maximum amount of chlorides and sulphates should not be more than [ A ] 0.15% and 4% by mass of cement respectively [ B ] 4% and 0.15% by mass of cement respectively [ C ] 0.30% and 2% by mass of cement respectively [ D ] 2% and 0.30% by mass of cement respectively
Last Answer : [ A ] 0.15% and 4% by mass of cement respectively
Description : Hardness of water is caused due to (A) Calcium sulphate (B) Magnesium sulphate (C) Calcium nitrates (D) All the above
Description : Pick out the wrong statement. (A) Eosin requirement in tallow soap is about 40-50% which fastens the lather formation, softens the hard soaps and increases its cleansing action (B) Soap powder is ... ., Benzotriazole) is added in soap to facilitate the removal of stains due to tea, blood etc
Last Answer : (D) Tarnish inhibitor (e.g., Benzotriazole) is added in soap to facilitate the removal of stains due to tea, blood etc
Description : Which of the following is responsible for permanent hardness of water? (1) magnesium bicarbonate (2) sodium chloride (3) calcium sulphate (4) calcium bicarbonate
Last Answer : (3) calcium sulphate Explanation: Permanent hardness is caused by dissolved calcium sulfate (which is not removed by boiling). Hard water contains dissolved magnesium and calcium ions. These make ... . Temporary hardness is caused by dissolved calcium hydrogen carbonate (which is removed by boiling)
Description : Zeolite removes both temporary as well as permanent hardness of water by precipitating calcium and magnesium present in water as insoluble zeolites. Used zeolite is regenerated by flushing with the solution of (A) Calcium sulphate (B) Sodium chloride (C) Sodium sulphate (D) Magnesium chloride
Last Answer : (B) Sodium chloride
Description : Which of the following is responsible for permanent hardness of water ? (1) magnesium bicarbonate (2) sodium chloride (3) calcium sulphate (4) calcium bicarbonate
Last Answer : calcium sulphate
Description : Metallic soap is __________ salt of fatty acids. (A) Sodium (B) Potassium (C) Both sodium & potassium (D) Aluminium or calcium
Last Answer : (D) Aluminium or calcium
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 : 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 : By boiling water, hardness can be removed if it is due to (A) Calcium sulphate (B) Magnesium sulphate (C) Calcium nitrate (D) Calcium bicarbonate
Last Answer : (D) Calcium bicarbonate
Description : State as to why: (a) A solution of Na2CO3 is alkaline? (b)alkali metals are prepared by electrolysis of their fused chlorides ? (c)sodium is found to be more useful than potassium ?
Last Answer : Ans. (a) It undergoes hydrolysis to produce a strong base NaOH . (b) When the aq. Solution of any alkali metal is subjected to electrolysis ,H2 instead of the alkali metal is produced at the ... of sugars and amino acids into the cells. Thus, sodium is found to be more useful than potassium.
Description : Which one of the following tests employs Ethylene Diamine Tetra Acetic Acid as a titrating agent? (a) Chlorides (b) Dissolved oxygen (c) Hardness (d) Residual chlorine
Last Answer : (c) Hardness
Description : The principal cation in intracellular fluid is (A) Sodium (B) Potassium (C) Calcium (D) Magnesium
Last Answer : Answer : B
Description : The principal cation in extracellular fluid is (A) Sodium (B) Potassium (C) Calcium (D) Magnesium
Last Answer : Answer : A
Description : The following ions help in enzymatic transfer of phosphate from ATP to pyruvic acid: (A) Sodium (B) Calcium (C) Magnesium (D) Potassium
Last Answer : Answer : D
Description : The action of digitalis is enhanced by (a) Sodium (b) Calcium (c) Magnesium (d) Potassium (e) Chloride
Last Answer : Ans: B
Description : Which of the following is involved in blood clotting? A. Sodium B. Magnesium C. Potassium D. Calcium
Last Answer : ANSWER: D
Description : __________ chloride present in crude petroleum as impurity is the most prolific producer of HCl during distillation. (A) Magnesium (B) Potassium (C) Calcium (D) Sodium
Last Answer : (A) Magnesium
Description : Name the ion responsible for unmasking of active sites for myosin for cross-bridge activity during muscle contraction. (a) Calcium (b) Magnesium (c) Sodium (d) Potassium
Last Answer : (a) Calcium
Description : Which is the principal cation in the plasma of the blood? (a) Potassium (b) Magnesium (c) Calcium (d) Sodium
Last Answer : d) Sodium
Description : Which of the following elements is responsible for maintaining turgor in cells? (a) Magnesium (b) Sodium (c) Potassium (d) Calcium
Last Answer : (c) Potassium
Description : Which of the following elements is responsible for maintaining turgor in cells ? (1) Magnesium (2) Sodium (3) Potassium (4) Calcium
Last Answer : (3) Potassium
Description : Permanent hardness of water, due to sulphates of the metal, can be destroyed by the use of (1) Nitrates (2) Zeolites (3) Sulphonates (4) None of these
Last Answer : (2) Zeolites Explanation: Zeolites are crystalline solids structures made of silicon, aluminum and oxygen that form a framework with cavities and channels inside where cations, water and/or small molecules may reside.
Description : Hard water for public water supply is discarded because (A) It consumes more soap (B) It contains lot of turbidity (C) It contains pathogenic bacterias (D) It possesses bad taste and odour
Last Answer : (A) It consumes more soap
Description : A water sample, which did not give lather with soap, was found to contain Ca(HCO3)2 and Mg(HCO3)2.
Last Answer : A water sample, which did not give lather with soap, was found to contain Ca(HCO3)2 and Mg ... with soap? Explain with the help of chemical reactions.
Description : Explain why hard water produces less lather with soap?
Last Answer : Ans- Hard water forms scum/precipitate with soap. Soap containing sodium stearate (C17H35COONa) reacts with hard water to precipitate out Ca/Mg stearate.
Description : Hard water (A) Does not affect the lather formation by soap (B) Is not unfit for drinking purpose (C) Pollutes the water stream (D) All (A), (B) and (C)
Last Answer : (B) Is not unfit for drinking purpose
Description : Why does the a bar of soap lather less when it gets smaller?
Last Answer : Less surface area?
Description : Why does soap lather less as it gets smaller?
Last Answer : It doesn't. When the bar is big, it's easy to hold and rub against a washcloth and it lathers easily. When small, it's hard to hold and develop the same friction. What my mother used to do was ... she would get them wet and mash them together and set aside to dry. The larger group was easier to use.
Description : Sulphur addition in soap is done to (A) Improve the soap texture (B) Cure pimples & dandruff (C) Fasten lather formation (D) Increase its cleansing action
Last Answer : (B) Cure pimples & dandruff