Advantages of synthetic detergents over soaps

Synthetic detergents have several advantages over soaps.

  1. Synthetic detergents can be used even in hard water whereas some of the soap gets wasted if the water is hard.
  2. Synthetic detergents can be used even in acidic medium as they are the salts of strong acids and are not decomposed in acidic medium.
  3. Synthetic detergents have a stronger cleansing action than soaps.
  4. Synthetic detergents  are more soluble in water than soaps.
  5. Synthetic detergents are prepared from the hydrocarbons obtained from petroleum. This saves vegetable oils which are otherwise used for making soaps
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Be the first to comment - What do you think?  Posted by admin - February 12, 2014 at 9:06 pm

Categories: AISSCE CHEMISTRY, CBSE Chemistry, CHEMISTRY IN EVERYDAY LIFE   Tags: , , , ,

Electrochemistry – Long Answer Type Questions (CBSE Class XII Chemistry)

Electrochemistry – Long Answer Type Questions

 

English: A revised copy of the Wikimedia Commo...

 

  1. What is galvanic cell?Explain the working of a galvanic cell by taking the example of Zn/CuSO4 reaction.Explain in brief the function of the salt bridge?
  2. What is electrode potential?describe the orgin of electrode potential when a metal strip is placed in a solution of its own ions.In what respects electrode potential differs from standard electrode potential?
  3. What do you understand by battery?Describe the chemistry of lead storage battery during its discharging and recharging process highlighting all the materials that are involved?
  4. What is corrosion of metals?How is rusting of iron envisaged as setting of electrochemical cell?Explain.Can a coating of tin over iron surface prevent rusting?Comment.
  5. What is meant by electrolytic conduction?On what factors does it depend?How does it differ from metallic conduction?
  6. Derive the relationship between (1) Conductivity and molar conductivity and (2)Standard cell potential and equilibrium constant?
  7. How does emf of a cell vary with temperature?Explain in brief?
  8. State and explain Kohlrausch law?How can it help to calculate (1) limiting molar conductivity of weak electrolyte and (2)degree of dissociation of weak electrolyte.
  9. How do you account for the variation of molar conductivity of weak and strong electrolytes with concentration?
  10. Iron does not rust when a coating of zinc cover its surface cracks in galvanised iron pipes , but it rusts rapidly when a coating of  tin done on its surface cracks.Explain.
  11. What is electrolysis?What role does electrode potential play while deciding the products of electrolysis?
  12. Write short note on (1)Hydrogen economy (2)Faradays-laws of electrolysis

 

 

 

 

 

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Prepare for AISSCE (CBSE Class XII) Chemistry through selected Long Answer Type Questions – Unit 2 – Solutions

AISSCE (CBSE Class XII) Chemistry through selected Long Answer Type Questions –

 

Unit 2 – Solutions

 

Solution Finding Stimulus-Behave as-if your so...

 

  1. What do you understand by vapour pressure of a liquid? How does it vary with temperature? Using pressure temperature curve show that what is normal boiling point and standard boiling point of a liquid?
  2. What is Vant Hoff’s factor? How is it related to degree of dissociation of the electrolyte in the solution? What is its value when the solute undergoes association?

 

 

 

 

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Prepare for AISSCE (CBSE Class XII) Chemistry through selected Long ANswer Type Questions – Unit 1 – The Solid State

Chapterwise long answer type questions for AISSCE (CBSE Class XII) Chemistry

Unit 1 – The Solid State

English: The face centered cubic crystal struc...

  1. Describe the following
    1. Hexagonal close packing
    2. Cubic close packing
    3. Body centred cubic packing
  2. What are the seven types of crystal systems? Give their unit cell dimensions. Draw structures of different types of unit cells which are possible for cubic crystal system.
  3. What do you mean by stoichiometric point defects? Describe briefly the various types of stoichiometric point defects.
  4. Explain the following.
    1. Schottky defect
    2. Frenkel defect
    3. F – centres
  5. Explain the conduction behaviour of metals, semiconductors and insulators on the basis of band theory of solids. What is the effect of increase of temperature on electrical conductivity of metals, semiconductors and insulators.
  6. Explain the following with suitable examples
    1. Paramagnetic substances
    2. ferrimagnetic substances
    3. Ferromagnetic substances

 

 

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Do you find it difficult to pass in Chemistry? Here are some tips to PASS!

Some students find it difficult to get pass marks in Chemistry. For them, here are some tips to get pass marks.

Chemistry generally contains three parts – inorganic, organic and physical. Most of the students find the organic part difficult to understand. It’s natural. It’s difficult to keep in mind all the formulas and equations of organic chemistry. But it’s just almost one third of the portion.

You can get more than 60% of marks by concentrating on Physical and inorganic portion.

SO, here’s a plan for those who want to pass marks in the available time.

Concentrate on Physical and inorganic part of chemistry without leaning any portion untouched. After you are confident about that, try to find out all named reactions, laws and principles.

A simple principle to follow is, learn thoroughly what you already know, then go to assimilate what you know partially.

If there are some portions you are not able to crack at all, you can leave it safely (unless it amounts to a major share)

Avoid learning new things, difficult  to understand portions in the last minute, but revise those portions which you have learnt already.

A cool mind is more productive.

Answer all questions.

This is a simple trick. If it happens by chance that some question has some error, then those attempted it will be benefitted.

Further, if you attempt the questions with an intention to score, some relevant points will also come into your answer and you may get some marks – say 1/2 or 1. These marks will add up to give you a pass marks.

So, attempt all questions with an intention to get maximum marks.

Lean all diagrams and draw them perfectly.

Be the first to comment - What do you think?  Posted by admin - February 7, 2014 at 6:09 am

Categories: CBSE Chemistry   Tags:

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