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Read the given passage and answer the question :
A sample of water which gives lather with soap with difficulty is known as hard water, while a sample of water which gives lather with soap easily is known as soft water. Hardness of water is due to the presence of bicarbonates, sulphates and chlorides of calcium and magnesium. Hardness of water is of two types, temporary and permanent hardness. When hardness of water is due to the presence of bicarbonates of magnesium and calcium, it is called temporary hardness. When hardness of water is due to the presence of sulphates and chlorides of magnesium and calcium, it is called permanent hardness.
The amount of hardness causing substances in a certain volume of water measures the extent of hardness or degree of hardness. Hardness of water is always calculated in terms of calcium carbonate although it is never responsible for causing hardness of water because of its insoluble nature. The reason for choosing calcium carbonate as the standard for calculating hardness of water is the ease in calculation as its molecular weight is exactly 100. Degree of hardness is usually expressed as parts per million (ppm).
Q. Why do soaps not form lather (foam) with hard water?
- a)Ca2+ and Mg2+ present in hard water form insoluble substances with soap.
- b)Ca2+ and Mg2+ present in hard water form soluble substance with soap
- c)HCO3− present in hard water form insoluble substance with soap
- d)SO42− present in hard water form soluble substance with soap
Correct answer is option 'A'. Can you explain this answer?
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Verified Answer
Read the given passage and answer the question :A sample of water whi...
The main cause of hardness of water is presence of Ca or Mg ions. When hard water containing these ions is treated with soap solution it reacts to form white crudy ppt known as scum.
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Most Upvoted Answer
Read the given passage and answer the question :A sample of water whi...
Reason for Soaps Not Forming Lather with Hard Water:
Formation of Insoluble Substances:
- The presence of Ca2+ and Mg2+ ions in hard water react with soap molecules to form insoluble substances like calcium and magnesium salts of fatty acids.
- These insoluble substances, commonly known as scum, do not allow the formation of lather or foam with soap.
Effect on Soap:
- When soap is mixed with hard water, the Ca2+ and Mg2+ ions combine with the soap molecules, preventing them from forming a stable lather.
- This results in reduced cleaning efficiency as the soap cannot effectively remove dirt and oils from surfaces.
Comparison with Soft Water:
- In contrast, soft water, which contains fewer Ca2+ and Mg2+ ions, allows soap molecules to interact freely and form lather easily.
- This leads to better cleaning performance and a more satisfying washing experience compared to hard water.
Conclusion:
- The presence of Ca2+ and Mg2+ ions in hard water is the primary reason why soaps do not form lather effectively, making cleaning tasks less efficient and requiring larger amounts of soap to compensate for the reduced lather formation.
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Read the given passage and answer the question :A sample of water which gives lather with soap with difficulty is known as hard water, while a sample of water which gives lather with soap easily is known as soft water. Hardness of water is due to the presence of bicarbonates, sulphates and chlorides of calcium and magnesium. Hardness of water is of two types, temporary and permanent hardness. When hardness of water is due to the presence of bicarbonates of magnesium and calcium, it is called temporary hardness. When hardness of water is due to the presence of sulphates and chlorides of magnesium and calcium, it is called permanent hardness.The amount of hardness causing substances in a certain volume of water measures the extent of hardness or degree of hardness. Hardness of water is always calculated in terms of calcium carbonate although it is never responsible for causing hardness of water because of its insoluble nature. The reason for choosing calcium carbonate as the standard for calculating hardness of water is the ease in calculation as its molecular weight is exactly 100. Degree of hardness is usually expressed as parts per million (ppm).Q. Why do soaps not form lather (foam) with hard water?a)Ca2+ and Mg2+ present in hard water form insoluble substances with soap.b)Ca2+ and Mg2+ present in hard water form soluble substance with soapc)HCO3− present in hard water form insoluble substance with soapd)SO42− present in hard water form soluble substance with soapCorrect answer is option 'A'. Can you explain this answer?
Question Description
Read the given passage and answer the question :A sample of water which gives lather with soap with difficulty is known as hard water, while a sample of water which gives lather with soap easily is known as soft water. Hardness of water is due to the presence of bicarbonates, sulphates and chlorides of calcium and magnesium. Hardness of water is of two types, temporary and permanent hardness. When hardness of water is due to the presence of bicarbonates of magnesium and calcium, it is called temporary hardness. When hardness of water is due to the presence of sulphates and chlorides of magnesium and calcium, it is called permanent hardness.The amount of hardness causing substances in a certain volume of water measures the extent of hardness or degree of hardness. Hardness of water is always calculated in terms of calcium carbonate although it is never responsible for causing hardness of water because of its insoluble nature. The reason for choosing calcium carbonate as the standard for calculating hardness of water is the ease in calculation as its molecular weight is exactly 100. Degree of hardness is usually expressed as parts per million (ppm).Q. Why do soaps not form lather (foam) with hard water?a)Ca2+ and Mg2+ present in hard water form insoluble substances with soap.b)Ca2+ and Mg2+ present in hard water form soluble substance with soapc)HCO3− present in hard water form insoluble substance with soapd)SO42− present in hard water form soluble substance with soapCorrect answer is option 'A'. Can you explain this answer? for Class 10 2024 is part of Class 10 preparation. The Question and answers have been prepared according to the Class 10 exam syllabus. Information about Read the given passage and answer the question :A sample of water which gives lather with soap with difficulty is known as hard water, while a sample of water which gives lather with soap easily is known as soft water. Hardness of water is due to the presence of bicarbonates, sulphates and chlorides of calcium and magnesium. Hardness of water is of two types, temporary and permanent hardness. When hardness of water is due to the presence of bicarbonates of magnesium and calcium, it is called temporary hardness. When hardness of water is due to the presence of sulphates and chlorides of magnesium and calcium, it is called permanent hardness.The amount of hardness causing substances in a certain volume of water measures the extent of hardness or degree of hardness. Hardness of water is always calculated in terms of calcium carbonate although it is never responsible for causing hardness of water because of its insoluble nature. The reason for choosing calcium carbonate as the standard for calculating hardness of water is the ease in calculation as its molecular weight is exactly 100. Degree of hardness is usually expressed as parts per million (ppm).Q. Why do soaps not form lather (foam) with hard water?a)Ca2+ and Mg2+ present in hard water form insoluble substances with soap.b)Ca2+ and Mg2+ present in hard water form soluble substance with soapc)HCO3− present in hard water form insoluble substance with soapd)SO42− present in hard water form soluble substance with soapCorrect answer is option 'A'. Can you explain this answer? covers all topics & solutions for Class 10 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Read the given passage and answer the question :A sample of water which gives lather with soap with difficulty is known as hard water, while a sample of water which gives lather with soap easily is known as soft water. Hardness of water is due to the presence of bicarbonates, sulphates and chlorides of calcium and magnesium. Hardness of water is of two types, temporary and permanent hardness. When hardness of water is due to the presence of bicarbonates of magnesium and calcium, it is called temporary hardness. When hardness of water is due to the presence of sulphates and chlorides of magnesium and calcium, it is called permanent hardness.The amount of hardness causing substances in a certain volume of water measures the extent of hardness or degree of hardness. Hardness of water is always calculated in terms of calcium carbonate although it is never responsible for causing hardness of water because of its insoluble nature. The reason for choosing calcium carbonate as the standard for calculating hardness of water is the ease in calculation as its molecular weight is exactly 100. Degree of hardness is usually expressed as parts per million (ppm).Q. Why do soaps not form lather (foam) with hard water?a)Ca2+ and Mg2+ present in hard water form insoluble substances with soap.b)Ca2+ and Mg2+ present in hard water form soluble substance with soapc)HCO3− present in hard water form insoluble substance with soapd)SO42− present in hard water form soluble substance with soapCorrect answer is option 'A'. Can you explain this answer?.
Read the given passage and answer the question :A sample of water which gives lather with soap with difficulty is known as hard water, while a sample of water which gives lather with soap easily is known as soft water. Hardness of water is due to the presence of bicarbonates, sulphates and chlorides of calcium and magnesium. Hardness of water is of two types, temporary and permanent hardness. When hardness of water is due to the presence of bicarbonates of magnesium and calcium, it is called temporary hardness. When hardness of water is due to the presence of sulphates and chlorides of magnesium and calcium, it is called permanent hardness.The amount of hardness causing substances in a certain volume of water measures the extent of hardness or degree of hardness. Hardness of water is always calculated in terms of calcium carbonate although it is never responsible for causing hardness of water because of its insoluble nature. The reason for choosing calcium carbonate as the standard for calculating hardness of water is the ease in calculation as its molecular weight is exactly 100. Degree of hardness is usually expressed as parts per million (ppm).Q. Why do soaps not form lather (foam) with hard water?a)Ca2+ and Mg2+ present in hard water form insoluble substances with soap.b)Ca2+ and Mg2+ present in hard water form soluble substance with soapc)HCO3− present in hard water form insoluble substance with soapd)SO42− present in hard water form soluble substance with soapCorrect answer is option 'A'. Can you explain this answer? for Class 10 2024 is part of Class 10 preparation. The Question and answers have been prepared according to the Class 10 exam syllabus. Information about Read the given passage and answer the question :A sample of water which gives lather with soap with difficulty is known as hard water, while a sample of water which gives lather with soap easily is known as soft water. Hardness of water is due to the presence of bicarbonates, sulphates and chlorides of calcium and magnesium. Hardness of water is of two types, temporary and permanent hardness. When hardness of water is due to the presence of bicarbonates of magnesium and calcium, it is called temporary hardness. When hardness of water is due to the presence of sulphates and chlorides of magnesium and calcium, it is called permanent hardness.The amount of hardness causing substances in a certain volume of water measures the extent of hardness or degree of hardness. Hardness of water is always calculated in terms of calcium carbonate although it is never responsible for causing hardness of water because of its insoluble nature. The reason for choosing calcium carbonate as the standard for calculating hardness of water is the ease in calculation as its molecular weight is exactly 100. Degree of hardness is usually expressed as parts per million (ppm).Q. Why do soaps not form lather (foam) with hard water?a)Ca2+ and Mg2+ present in hard water form insoluble substances with soap.b)Ca2+ and Mg2+ present in hard water form soluble substance with soapc)HCO3− present in hard water form insoluble substance with soapd)SO42− present in hard water form soluble substance with soapCorrect answer is option 'A'. Can you explain this answer? covers all topics & solutions for Class 10 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Read the given passage and answer the question :A sample of water which gives lather with soap with difficulty is known as hard water, while a sample of water which gives lather with soap easily is known as soft water. Hardness of water is due to the presence of bicarbonates, sulphates and chlorides of calcium and magnesium. Hardness of water is of two types, temporary and permanent hardness. When hardness of water is due to the presence of bicarbonates of magnesium and calcium, it is called temporary hardness. When hardness of water is due to the presence of sulphates and chlorides of magnesium and calcium, it is called permanent hardness.The amount of hardness causing substances in a certain volume of water measures the extent of hardness or degree of hardness. Hardness of water is always calculated in terms of calcium carbonate although it is never responsible for causing hardness of water because of its insoluble nature. The reason for choosing calcium carbonate as the standard for calculating hardness of water is the ease in calculation as its molecular weight is exactly 100. Degree of hardness is usually expressed as parts per million (ppm).Q. Why do soaps not form lather (foam) with hard water?a)Ca2+ and Mg2+ present in hard water form insoluble substances with soap.b)Ca2+ and Mg2+ present in hard water form soluble substance with soapc)HCO3− present in hard water form insoluble substance with soapd)SO42− present in hard water form soluble substance with soapCorrect answer is option 'A'. Can you explain this answer?.
Solutions for Read the given passage and answer the question :A sample of water which gives lather with soap with difficulty is known as hard water, while a sample of water which gives lather with soap easily is known as soft water. Hardness of water is due to the presence of bicarbonates, sulphates and chlorides of calcium and magnesium. Hardness of water is of two types, temporary and permanent hardness. When hardness of water is due to the presence of bicarbonates of magnesium and calcium, it is called temporary hardness. When hardness of water is due to the presence of sulphates and chlorides of magnesium and calcium, it is called permanent hardness.The amount of hardness causing substances in a certain volume of water measures the extent of hardness or degree of hardness. Hardness of water is always calculated in terms of calcium carbonate although it is never responsible for causing hardness of water because of its insoluble nature. The reason for choosing calcium carbonate as the standard for calculating hardness of water is the ease in calculation as its molecular weight is exactly 100. Degree of hardness is usually expressed as parts per million (ppm).Q. Why do soaps not form lather (foam) with hard water?a)Ca2+ and Mg2+ present in hard water form insoluble substances with soap.b)Ca2+ and Mg2+ present in hard water form soluble substance with soapc)HCO3− present in hard water form insoluble substance with soapd)SO42− present in hard water form soluble substance with soapCorrect answer is option 'A'. Can you explain this answer? in English & in Hindi are available as part of our courses for Class 10.
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Here you can find the meaning of Read the given passage and answer the question :A sample of water which gives lather with soap with difficulty is known as hard water, while a sample of water which gives lather with soap easily is known as soft water. Hardness of water is due to the presence of bicarbonates, sulphates and chlorides of calcium and magnesium. Hardness of water is of two types, temporary and permanent hardness. When hardness of water is due to the presence of bicarbonates of magnesium and calcium, it is called temporary hardness. When hardness of water is due to the presence of sulphates and chlorides of magnesium and calcium, it is called permanent hardness.The amount of hardness causing substances in a certain volume of water measures the extent of hardness or degree of hardness. Hardness of water is always calculated in terms of calcium carbonate although it is never responsible for causing hardness of water because of its insoluble nature. The reason for choosing calcium carbonate as the standard for calculating hardness of water is the ease in calculation as its molecular weight is exactly 100. Degree of hardness is usually expressed as parts per million (ppm).Q. Why do soaps not form lather (foam) with hard water?a)Ca2+ and Mg2+ present in hard water form insoluble substances with soap.b)Ca2+ and Mg2+ present in hard water form soluble substance with soapc)HCO3− present in hard water form insoluble substance with soapd)SO42− present in hard water form soluble substance with soapCorrect answer is option 'A'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
Read the given passage and answer the question :A sample of water which gives lather with soap with difficulty is known as hard water, while a sample of water which gives lather with soap easily is known as soft water. Hardness of water is due to the presence of bicarbonates, sulphates and chlorides of calcium and magnesium. Hardness of water is of two types, temporary and permanent hardness. When hardness of water is due to the presence of bicarbonates of magnesium and calcium, it is called temporary hardness. When hardness of water is due to the presence of sulphates and chlorides of magnesium and calcium, it is called permanent hardness.The amount of hardness causing substances in a certain volume of water measures the extent of hardness or degree of hardness. Hardness of water is always calculated in terms of calcium carbonate although it is never responsible for causing hardness of water because of its insoluble nature. The reason for choosing calcium carbonate as the standard for calculating hardness of water is the ease in calculation as its molecular weight is exactly 100. Degree of hardness is usually expressed as parts per million (ppm).Q. Why do soaps not form lather (foam) with hard water?a)Ca2+ and Mg2+ present in hard water form insoluble substances with soap.b)Ca2+ and Mg2+ present in hard water form soluble substance with soapc)HCO3− present in hard water form insoluble substance with soapd)SO42− present in hard water form soluble substance with soapCorrect answer is option 'A'. Can you explain this answer?, a detailed solution for Read the given passage and answer the question :A sample of water which gives lather with soap with difficulty is known as hard water, while a sample of water which gives lather with soap easily is known as soft water. Hardness of water is due to the presence of bicarbonates, sulphates and chlorides of calcium and magnesium. Hardness of water is of two types, temporary and permanent hardness. When hardness of water is due to the presence of bicarbonates of magnesium and calcium, it is called temporary hardness. When hardness of water is due to the presence of sulphates and chlorides of magnesium and calcium, it is called permanent hardness.The amount of hardness causing substances in a certain volume of water measures the extent of hardness or degree of hardness. Hardness of water is always calculated in terms of calcium carbonate although it is never responsible for causing hardness of water because of its insoluble nature. The reason for choosing calcium carbonate as the standard for calculating hardness of water is the ease in calculation as its molecular weight is exactly 100. Degree of hardness is usually expressed as parts per million (ppm).Q. Why do soaps not form lather (foam) with hard water?a)Ca2+ and Mg2+ present in hard water form insoluble substances with soap.b)Ca2+ and Mg2+ present in hard water form soluble substance with soapc)HCO3− present in hard water form insoluble substance with soapd)SO42− present in hard water form soluble substance with soapCorrect answer is option 'A'. Can you explain this answer? has been provided alongside types of Read the given passage and answer the question :A sample of water which gives lather with soap with difficulty is known as hard water, while a sample of water which gives lather with soap easily is known as soft water. Hardness of water is due to the presence of bicarbonates, sulphates and chlorides of calcium and magnesium. Hardness of water is of two types, temporary and permanent hardness. When hardness of water is due to the presence of bicarbonates of magnesium and calcium, it is called temporary hardness. When hardness of water is due to the presence of sulphates and chlorides of magnesium and calcium, it is called permanent hardness.The amount of hardness causing substances in a certain volume of water measures the extent of hardness or degree of hardness. Hardness of water is always calculated in terms of calcium carbonate although it is never responsible for causing hardness of water because of its insoluble nature. The reason for choosing calcium carbonate as the standard for calculating hardness of water is the ease in calculation as its molecular weight is exactly 100. Degree of hardness is usually expressed as parts per million (ppm).Q. Why do soaps not form lather (foam) with hard water?a)Ca2+ and Mg2+ present in hard water form insoluble substances with soap.b)Ca2+ and Mg2+ present in hard water form soluble substance with soapc)HCO3− present in hard water form insoluble substance with soapd)SO42− present in hard water form soluble substance with soapCorrect answer is option 'A'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice Read the given passage and answer the question :A sample of water which gives lather with soap with difficulty is known as hard water, while a sample of water which gives lather with soap easily is known as soft water. Hardness of water is due to the presence of bicarbonates, sulphates and chlorides of calcium and magnesium. Hardness of water is of two types, temporary and permanent hardness. When hardness of water is due to the presence of bicarbonates of magnesium and calcium, it is called temporary hardness. When hardness of water is due to the presence of sulphates and chlorides of magnesium and calcium, it is called permanent hardness.The amount of hardness causing substances in a certain volume of water measures the extent of hardness or degree of hardness. Hardness of water is always calculated in terms of calcium carbonate although it is never responsible for causing hardness of water because of its insoluble nature. The reason for choosing calcium carbonate as the standard for calculating hardness of water is the ease in calculation as its molecular weight is exactly 100. Degree of hardness is usually expressed as parts per million (ppm).Q. Why do soaps not form lather (foam) with hard water?a)Ca2+ and Mg2+ present in hard water form insoluble substances with soap.b)Ca2+ and Mg2+ present in hard water form soluble substance with soapc)HCO3− present in hard water form insoluble substance with soapd)SO42− present in hard water form soluble substance with soapCorrect answer is option 'A'. Can you explain this answer? tests, examples and also practice Class 10 tests.
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