Explain the formation of scum when hard water is treated with soap.

Question:

Answer:

Calcium and magnesium ions are present in the hard water. These ions react with soap to form scum. The sum is an insoluble substance which appears as white, off-white, or sticky layer on water surface. The formation of the scum reduces the soap's effectiveness.

Chemical Reaction

Sodium and potassium ion present in the soap molecules are displaced by the magnesium and calcium ions present in the hard water resulting in formation of scum. It reduces the soap's cleansing properties.

Reaction

RCOO^-Na⁺ + Ca²⁺ → (RCOO^-)₂Ca + 2Na⁺

RCOO^-Na⁺ + Mg²⁺ → (RCOO^-)₂Mg + 2Na⁺

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Explain the mechanism of the cleaning action of soaps.

Give a test that can be used to differentiate between saturated and unsaturated hydrocarbons

Which of the following hydrocarbons undergo addition reactions: C2H6, C3H8, C3H6, C2H2 and CH4

What is Hydrogenation? What is its industrial application?

What change will you observe if you test soap with litmus paper (red and blue)?

Why are carbon and its compounds used as fuels for most applications?

Why does micelle formation take place when soap is added to water? Will a micelle be formed in other solvents such as ethanol also?

How can ethanol and ethanoic acid be differentiated on the basis of their physical and chemical properties?

What is homologous series? Explain with an example.

Draw the electron dot structures for : (a) ethanoic acid (b) H2S (c) propanone (d) F2

Explain the nature of the covalent bond using the bond formation in CH3Cl.

While cooking, if the bottom of the vessel is getting blackened on the outside, it means that (a) the food is not cooked completely. (b) the fuel is not burning completely. (c) the fuel is wet. (d) the fuel is burning completely.

Butanone is a four-carbon compound with the functional group : (a) carboxylic acid (b) aldehyde (c) ketone (d) alcohol

Ethane, with the molecular formula C2H6 has (a) 6 covalent bonds. (b) 7 covalent bonds. (c) 8 covalent bonds. (d) 9 covalent bonds.

What are functional groups?

Would you be able to check if water is hard by using a detergent?

What are oxidising agents?

How would you distinguish experimentally between an alcohol and a carboxylic acid?

A mixture of oxygen and ethyne is burnt for welding. Can you tell why a mixture of ethyne and air is not used?

Write two properties of covalent compounds.

How would you name the following compounds?

Draw the structures for the following compounds : (i) Ethanoic acid (ii) Bromopentane* (iii) Butanone (iv) Hexanal. *Are structural isomers possible for bromopentane.

What will be the formula and electron dot structure of cyclopentane?

What are the two properties of carbon which lead to the huge number of carbon compounds we see around us?

How many structural isomers can you draw for pentane?

What would be the electron dot structure of a molecule of sulphur which is made up of eight atoms of sulphur? (Hint : The eight atoms of sulphur are joined together in the form of a ring.)

Chapter 4 NCERT Class 10 Science SOLUTIONS

Question:

Answer:

More NCERT Questions

Explain the mechanism of the cleaning action of soaps.

Give a test that can be used to differentiate between saturated and unsaturated hydrocarbons

Which of the following hydrocarbons undergo addition reactions: C2H6, C3H8, C3H6, C2H2 and CH4

What is Hydrogenation? What is its industrial application?

What change will you observe if you test soap with litmus paper (red and blue)?

Why are carbon and its compounds used as fuels for most applications?

Why does micelle formation take place when soap is added to water? Will a micelle be formed in other solvents such as ethanol also?

How can ethanol and ethanoic acid be differentiated on the basis of their physical and chemical properties?

What is homologous series? Explain with an example.

Draw the electron dot structures for : (a) ethanoic acid (b) H2S (c) propanone (d) F2

Explain the nature of the covalent bond using the bond formation in CH3Cl.

While cooking, if the bottom of the vessel is getting blackened on the outside, it means that (a) the food is not cooked completely. (b) the fuel is not burning completely. (c) the fuel is wet. (d) the fuel is burning completely.

Butanone is a four-carbon compound with the functional group : (a) carboxylic acid (b) aldehyde (c) ketone (d) alcohol

Ethane, with the molecular formula C2H6 has (a) 6 covalent bonds. (b) 7 covalent bonds. (c) 8 covalent bonds. (d) 9 covalent bonds.

What are functional groups?

Would you be able to check if water is hard by using a detergent?

What are oxidising agents?

How would you distinguish experimentally between an alcohol and a carboxylic acid?

A mixture of oxygen and ethyne is burnt for welding. Can you tell why a mixture of ethyne and air is not used?

Write two properties of covalent compounds.

How would you name the following compounds?

Draw the structures for the following compounds : (i) Ethanoic acid (ii) Bromopentane* (iii) Butanone (iv) Hexanal. *Are structural isomers possible for bromopentane.

What will be the formula and electron dot structure of cyclopentane?

What are the two properties of carbon which lead to the huge number of carbon compounds we see around us?

How many structural isomers can you draw for pentane?

What would be the electron dot structure of a molecule of sulphur which is made up of eight atoms of sulphur? (Hint : The eight atoms of sulphur are joined together in the form of a ring.)

What would be the electron dot structure of carbon dioxide which has the formula CO2?

Related Topics

Chapter 4 NCERT Class 10 Science SOLUTIONS

Question:

Answer:

More NCERT Questions

Explain the mechanism of the cleaning action of soaps.

Give a test that can be used to differentiate between saturated and unsaturated hydrocarbons

Which of the following hydrocarbons undergo addition reactions: C2H6, C3H8, C3H6, C2H2 and CH4

What is Hydrogenation? What is its industrial application?

What change will you observe if you test soap with litmus paper (red and blue)?

Why are carbon and its compounds used as fuels for most applications?

Why does micelle formation take place when soap is added to water? Will a micelle be formed in other solvents such as ethanol also?

How can ethanol and ethanoic acid be differentiated on the basis of their physical and chemical properties?

What is homologous series? Explain with an example.

Draw the electron dot structures for : (a) ethanoic acid (b) H2S (c) propanone (d) F2

Explain the nature of the covalent bond using the bond formation in CH3Cl.

While cooking, if the bottom of the vessel is getting blackened on the outside, it means that (a) the food is not cooked completely. (b) the fuel is not burning completely. (c) the fuel is wet. (d) the fuel is burning completely.

Butanone is a four-carbon compound with the functional group : (a) carboxylic acid (b) aldehyde (c) ketone (d) alcohol

Ethane, with the molecular formula C2H6 has (a) 6 covalent bonds. (b) 7 covalent bonds. (c) 8 covalent bonds. (d) 9 covalent bonds.

What are functional groups?

Would you be able to check if water is hard by using a detergent?

What are oxidising agents?

How would you distinguish experimentally between an alcohol and a carboxylic acid?

A mixture of oxygen and ethyne is burnt for welding. Can you tell why a mixture of ethyne and air is not used?

Write two properties of covalent compounds.

How would you name the following compounds?

Draw the structures for the following compounds : (i) Ethanoic acid (ii) Bromopentane* (iii) Butanone (iv) Hexanal. *Are structural isomers possible for bromopentane.

What will be the formula and electron dot structure of cyclopentane?

What are the two properties of carbon which lead to the huge number of carbon compounds we see around us?

How many structural isomers can you draw for pentane?

What would be the electron dot structure of a molecule of sulphur which is made up of eight atoms of sulphur? (Hint : The eight atoms of sulphur are joined together in the form of a ring.)

What would be the electron dot structure of carbon dioxide which has the formula CO2?

Related Topics

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