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

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
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(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 because magnesium ions or calcium ions present in hard water react with soap to form calcium stearate or magnesium stearate and thus forms scum.
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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

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 : Formation of lather with soap

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 : 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 

Last Answer : (C) Presence of bicarbonates, sulphates or chlorides of calcium and magnesium 

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 prepared by mixing soap with hydrated sodium carbonate (C) Detergents differ from soaps in their action in hard water (D) Tarnish inhibitor (e.g., Benzotriazole) is added in soap to facilitate the removal of stains due to tea, blood etc

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

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)

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

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

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

(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 react with those in soap, leaving an insoluble film. Detergents react less to minerals in water and for all practical purposes are the product of choice for laundry, unless you have very soft water. On the other hand, soap will combine with the magnesium and calcium ions in hard water to create an insoluble residue that can clog drains and stick to clothing.

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

(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 react with those in soap, leaving an insoluble film. Detergents react less to minerals in water and for all practical purposes are the product of choice for laundry, unless you have very soft water. On the other hand, soap will combine with the magnesium and calcium ions in hard water to create an insoluble residue that can clog drains and stick to clothing.

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

Explain why hard water produces less lather with soap?

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.

Permanent hardness of water cannot be removed by (a) Boiling (b) Adding caustic soda (c) Distillation (d) Adding soda

Description : Permanent hardness of water cannot be removed by (a) Boiling (b) Adding caustic soda (c) Distillation (d) Adding soda

Last Answer : Ans:(a)

Which of the following processes can remove both temporary as well as permanent hardness of water? (A) Filtration (B) Boiling (C) Distillation (D) None of these

Description : Which of the following processes can remove both temporary as well as permanent hardness of water? (A) Filtration (B) Boiling (C) Distillation (D) None of these

Last Answer : (C) Distillation

A water sample, which did not give lather with soap, was found to contain Ca(HCO3)2 and Mg(HCO3)2.

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.

Why does the a bar of soap lather less when it gets smaller?

Description : Why does the a bar of soap lather less when it gets smaller?

Last Answer : Less surface area?

Why does soap lather less as it gets smaller?

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.

Pick out the correct statement. (A) Ponchan-Savarit method is more accurate than McCabe-Thiele method to determine the number of theoretical stages required for the separation of non￾ideal binary system by distillation (B) A sharp decrease in pressure drop is an indication of flooding in a distillation coloumn (C) Solvent used in extractive distillation should be of high volatility (D) Flash distillation is suitable for separating components which have very close boiling temperature

Description : Pick out the correct statement. (A) Ponchan-Savarit method is more accurate than McCabe-Thiele method to determine the number of theoretical stages required for the separation of ... Flash distillation is suitable for separating components which have very close boiling temperature

Last Answer : (A) Ponchan-Savarit method is more accurate than McCabe-Thiele method to determine the number of theoretical stages required for the separation of non￾ideal binary system by distillation

A liquid with high boiling point decomposes on simple distillation but it can be steam distilled for its purification .Explain how is it possible?

Description : A liquid with high boiling point decomposes on simple distillation but it can be steam distilled for its purification .Explain how is it possible?

Last Answer : In steam distillation boiling occurs when vapour pressure of organic compound & steam becomes equal to atmospheric pressure. As vapour pressure of water is higher than the organic liquid. ... organic liquid vaporizes at a temperature below its boiling point in steam distillation without decomposing.

Two liquids (A)and(B)are separated by fractional distillation, the boiling point of (A) is less than (B).which liquid comes out first in distillate? Explain.

Description : Two liquids (A)and(B)are separated by fractional distillation, the boiling point of (A) is less than (B).which liquid comes out first in distillate? Explain.

Last Answer : The liquid (a) comes out first in distillate. On boiling the vapours of lower boiling component are formed first.

Explain ,why an organic liquid vapourises at a temperature below its boiling point in steam distillation?

Description : Explain ,why an organic liquid vapourises at a temperature below its boiling point in steam distillation?

Last Answer : Because for boiling to occur vapour pressure of organic compound & steam should be equal to atmospheric pressure. As vapour pressure of water is higher than organic liquid. Therefore, organic liquid vaporizes at a temperature below its boiling point in steam distillation .

The noble gases have low boiling points because: w) their ionization potentials are very low x) only weak Van der Waals forces hold the atoms together y) they are produced by the fractional distillation of liquid air z) they have eight electrons in the outer shell

Description : The noble gases have low boiling points because: w) their ionization potentials are very low x) only weak Van der Waals forces hold the atoms together y) they are produced by the fractional distillation of liquid air z) they have eight electrons in the outer shell

Last Answer : ANSWER: X -- ONLY WEAK VAN DER WAALS FORCES HOLD THE ATOMS TOGETHER

The advantage of detergents over soaps is (1) Detergents are soluble in water (2) Detergents could not give much lather (3) Detergents give lather even with hard water (4) Soaps give lather with only soft water

Description : The advantage of detergents over soaps is (1) Detergents are soluble in water (2) Detergents could not give much lather (3) Detergents give lather even with hard water (4) Soaps give lather with only soft water

Last Answer : Detergents give lather even with hard water

Soap is prepared by boiling caustic soda with – (1) Alcohol (2) Kerosene oil (3) Glycerine (4) Fats

Description : Soap is prepared by boiling caustic soda with – (1) Alcohol (2) Kerosene oil (3) Glycerine (4) Fats

Last Answer : (4) Fats Explanation: The most basic kind of soap is made from cuastic soda and animal fat. The two are heated together, and then cooled. The process is called "saponification". In technical ... hydrolysis of triglyeerides which are esters of fatty acids, to form the sodium salt, of a carboxylate.

Soap is prepared by boiling caustic soda with (1) Alcohol (2) Kerosene oil (3) Glycerine (4) Fats

Description : Soap is prepared by boiling caustic soda with (1) Alcohol (2) Kerosene oil (3) Glycerine (4) Fats

Last Answer : Fats

Metallic soap (e.g. aluminium or calcium salts of fatty acids) can be used (A) As a lubrican(B) As a rust preventive(C) In hard water for cleaning of cloth(D) As a foam depressant in distillation column

Description : Metallic soap (e.g. aluminium or calcium salts of fatty acids) can be used (A) As a lubrican (B) As a rust preventive (C) In hard water for cleaning of cloth (D) As a foam depressant in distillation column

Last Answer : (A) As a lubricant

Large scale usage of flash distillation is practised in (A) Soap manufacturing (B) Ammonia synthesis plant (C) Polymerisation industry (D) Petroleum refining

Description : Large scale usage of flash distillation is practised in (A) Soap manufacturing (B) Ammonia synthesis plant (C) Polymerisation industry (D) Petroleum refining

Last Answer : (D) Petroleum refining

Temporary hardness of water can be removed by (A) Addition of alum (a coagulant) (B) Boiling (C) Filtration (through gravity sand filter) (D) Addition of lime

Description : Temporary hardness of water can be removed by (A) Addition of alum (a coagulant) (B) Boiling (C) Filtration (through gravity sand filter) (D) Addition of lime

Last Answer : (B) Boiling

Permanent hardness of water can be removed by (A) Simply boiling (B) Adding alum (C) Passing it through cation & anion exchangers (D) All (A), (B) and (C)

Description : Permanent hardness of water can be removed by (A) Simply boiling (B) Adding alum (C) Passing it through cation & anion exchangers (D) All (A), (B) and (C)

Last Answer : (C) Passing it through cation & anion exchangers

Permanent hardness of water can be removed by (A) Boiling (B) Adding Ca(OH)2 (C) Boiling it with Na2CO3 (D) None of these

Description : Permanent hardness of water can be removed by (A) Boiling (B) Adding Ca(OH)2 (C) Boiling it with Na2CO3 (D) None of these

Last Answer : (C) Boiling it with Na2CO3

The temporary hardness of water can be removed by (A) Boiling (B) Adding lime (C) Adding alum (D) Filtration

Description : The temporary hardness of water can be removed by (A) Boiling (B) Adding lime (C) Adding alum (D) Filtration

Last Answer : (A) Boiling

By boiling water, hardness can be removed if it is due to (A) Calcium sulphate (B) Magnesium sulphate (C) Calcium nitrate (D) Calcium bicarbonate

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 

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

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 

Steam distillation is not recommended to be used, if the (A) Azeotropic mixture is to be separated and the final product is miscible with water (B) Liquids decompose, if distilled directly at atmospheric pressure (C) Material cannot be distilled by indirect heating even under low pressure, because of the high boiling temperature (D) Material to be distilled is thermally unstable or has the tendency to react with other components associated with it, at the boiling temperature

Description : Steam distillation is not recommended to be used, if the (A) Azeotropic mixture is to be separated and the final product is miscible with water (B) Liquids decompose, if ... unstable or has the tendency to react with other components associated with it, at the boiling temperature

Last Answer : (A) Azeotropic mixture is to be separated and the final product is miscible with water

steam distillation, the (A) Temperature is 100°C(B) Temperature is more than 100° C (C) Product must be immiscible with water (D) Temperature is higher than the boiling point of either component

Description : steam distillation, the (A) Temperature is 100°C(B) Temperature is more than 100° C (C) Product must be immiscible with water (D) Temperature is higher than the boiling point of either component

Last Answer : (C) Product must be immiscible with water

_________ of test specimens is not involved in any hardness testing method. (A) Fracture (B) Indentation (C) Wear (D) Scratch

Description : _________ of test specimens is not involved in any hardness testing method. (A) Fracture (B) Indentation (C) Wear (D) Scratch

Last Answer : (A) Fracture

. A dilute aqueous solution is to be concentrated in an evaporator system. High pressure steam is available. Multiple effect evaporator system is employed, because (A) Total heat transfer area of all the effects is -less than that in a single effect evaporator system (B) Total amount of vapor produced per Kg of feed steam in a multiple effect system is much higher than in a single effect (C) Boiling point elevation in a single effect system is much higher than that in any effect in a multi-effect system (D) Heat transfer co-efficient in a single effect is much lower than that in any effect in a multi-effect system

Description : . A dilute aqueous solution is to be concentrated in an evaporator system. High pressure steam is available. Multiple effect evaporator system is employed, because (A) Total heat transfer area of ... in a single effect is much lower than that in any effect in a multi-effect system

Last Answer : (B) Total amount of vapor produced per Kg of feed steam in a multiple effect system is much higher than in a single effect

Distillation at reduced pressure is used for liquids which (a) Have high boiling points (b) Have low boiling points (c) Have high volatility (d) Decompose before their boiling points

Description : Distillation at reduced pressure is used for liquids which (a) Have high boiling points (b) Have low boiling points (c) Have high volatility (d) Decompose before their boiling points

Last Answer : Ans:(d)

Crude oil is subjected to vacuum distillation in the last stage, because (A) High boiling point products like heavy fuel oil & lubricating oils are heat sensitive and may decompose (B) Lighter/low boiling products are prone to thermal decomposition (C) High purity products can be obtained thereby (D) None of these

Description : Crude oil is subjected to vacuum distillation in the last stage, because (A) High boiling point products like heavy fuel oil & lubricating oils are heat sensitive and may decompose (B) Lighter/low ... prone to thermal decomposition (C) High purity products can be obtained thereby (D) None of these

Last Answer : (A) High boiling point products like heavy fuel oil & lubricating oils are heat sensitive and may decompose

Products drawn from the top to bottom of the crude oil distillation column has progressively increasing (A) Boiling points (B) Molecular weight (C) C/H ratio (D) All (A), (B) and (C)

Description : Products drawn from the top to bottom of the crude oil distillation column has progressively increasing (A) Boiling points (B) Molecular weight (C) C/H ratio (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Solvent naphtha' used mostly as a solvent in paints and perfumery is produced by the __________ of virgin naphtha into small boiling range cuts. (A) Steam reforming (B) Distillation (C) Desulphurisation (D) None of these

Description : Solvent naphtha' used mostly as a solvent in paints and perfumery is produced by the __________ of virgin naphtha into small boiling range cuts. (A) Steam reforming (B) Distillation (C) Desulphurisation (D) None of these

Last Answer : (B) Distillation

Solvent used in extractive distillation (A) Is of low volatility (B) Forms a low boiling azeotrope (C) Forms a high boiling azeotrope (D) Does not alter the relative volatility of the original components

Description : Solvent used in extractive distillation (A) Is of low volatility (B) Forms a low boiling azeotrope (C) Forms a high boiling azeotrope (D) Does not alter the relative volatility of the original components

Last Answer : (B) Forms a low boiling azeotrope

Entrainer used in Azeotropic distillation should (A) Form a low boiling azeotrope with one of the constituents of the mixture (B) Form a new azeotrope of low relative volatility with one of the constituents of the mixture (C) Have high latent heat of vaporisation (D) Have high viscosity to provide high tray efficiency

Description : Entrainer used in Azeotropic distillation should (A) Form a low boiling azeotrope with one of the constituents of the mixture (B) Form a new azeotrope of low relative volatility with one of the ... (C) Have high latent heat of vaporisation (D) Have high viscosity to provide high tray efficiency

Last Answer : (A) Form a low boiling azeotrope with one of the constituents of the mixture

Components, having widely different boiling point in a binary mixture, can be separated using __________ distillation. (A) Molecular (B) Extractive (C) Steam (D) Simple

Description : Components, having widely different boiling point in a binary mixture, can be separated using __________ distillation. (A) Molecular (B) Extractive (C) Steam (D) Simple

Last Answer : (D) Simple

Flash distillation is suitable for separating the constituents of a binary system, which (A) Form minimum boiling azeotrope (B) Have very wide boiling points (C) Have very close boiling points (D) Form constant boiling azeotrope

Description : Flash distillation is suitable for separating the constituents of a binary system, which (A) Form minimum boiling azeotrope (B) Have very wide boiling points (C) Have very close boiling points (D) Form constant boiling azeotrope

Last Answer : (B) Have very wide boiling points

Steam distillation is used for separation of high boiling (A) Substances from non-volatile impurities (B) Volatile impurity from still higher boiling substances (C) Both (A) and (B) (D) Neither (A) nor (B)

Description : Steam distillation is used for separation of high boiling (A) Substances from non-volatile impurities (B) Volatile impurity from still higher boiling substances (C) Both (A) and (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) and (B)

Flash distillation is suitable for the separation of components (A) Having very close boiling points (B) Which form maximum boiling azeotrope (C) Having very wide boiling points (D) Which form minimum boiling azeotrope

Description : Flash distillation is suitable for the separation of components (A) Having very close boiling points (B) Which form maximum boiling azeotrope (C) Having very wide boiling points (D) Which form minimum boiling azeotrope

Last Answer : (C) Having very wide boiling points

When the mixture to be distilled has a very high boiling point and the product material is heat sensitive, the separation technique to be used is __________ distillation. (A) Continuous (B) Steam (C) Azeotropic (D) None of these

Description : When the mixture to be distilled has a very high boiling point and the product material is heat sensitive, the separation technique to be used is __________ distillation. (A) Continuous (B) Steam (C) Azeotropic (D) None of these

Last Answer : (B) Steam

Pick out the wrong statement. (A) In case of heat transfer by purely forced convection, GR /Re 2 ≤ 1 (B) The equivalent diameter of heat transfer for a duct of square cross￾section (having each side as 'x') is equal to 4x (C) Distillation process is not the same as evaporation (D) The effectiveness of nucleate boiling depends basically on the ease with which the bubbles are formed and detached from the heating surface

Description : Pick out the wrong statement. (A) In case of heat transfer by purely forced convection, GR /Re 2 ≤ 1 (B) The equivalent diameter of heat transfer for a duct of ... nucleate boiling depends basically on the ease with which the bubbles are formed and detached from the heating surface

Last Answer : (B) The equivalent diameter of heat transfer for a duct of square cross￾section (having each side as 'x') is equal to 4x

Oxygen is separated by distillation from air after its liquefaction. The boiling point of oxygen is about __________ °C. (A) -83 (B) -183 (C) -196 (D) -218

Description : Oxygen is separated by distillation from air after its liquefaction. The boiling point of oxygen is about __________ °C. (A) -83 (B) -183 (C) -196 (D) -218

Last Answer : (B) -183

The distillation carried out in such a way that the liquid with the lowest boiling point is first evaporated and recondensed, then the liquid with the next higher boiling point is then evaporated and recondensed, and so on until all the available liquid fuels are separately recovered in the sequence of their boiling points. Such a process is called  A. cracking  B. carbonisation  C. fractional distillation  D. full distillation

Description : The distillation carried out in such a way that the liquid with the lowest boiling point is first evaporated and recondensed, then the liquid with the next higher boiling point is then evaporated and ... is called  A. cracking  B. carbonisation  C. fractional distillation  D. full distillation

Last Answer : Answer: C

Saponification of a fat (a) always results in the formation of insoluble soaps (b) produces glycerol and soap (c) is used in the production of detergents (d) is used in the production of lactic acid

Description : Saponification of a fat (a) always results in the formation of insoluble soaps (b) produces glycerol and soap (c) is used in the production of detergents (d) is used in the production of lactic acid

Last Answer : produces glycerol and soap

Consider the following statements: 1. Detergents do not produce lather with hard water 2. Water gas is a mixture of carbon monoxide and hydrogen 3. Methane is the chief constituent of CNG 4. LPG contains mainly n-butane 5. The correct statements are: (a) 1, 2 and 4 only (b) 1,3 and 4 only (c) 2, 3 and 4 only (d) 1, 2 and 3 only

Description : Consider the following statements: 1. Detergents do not produce lather with hard water 2. Water gas is a mixture of carbon monoxide and hydrogen 3. Methane is the chief constituent of CNG 4. LPG contains mainly n-butane 5. The correct ... (b) 1,3 and 4 only (c) 2, 3 and 4 only (d) 1, 2 and 3 only

Last Answer : Ans:(c)

Name the method used to remove temporary hardness of water?

Description : Name the method used to remove temporary hardness of water?

Last Answer : Ans-Clark s method OR By Boiling