Home
Class 12
CHEMISTRY
Addition of H2 to acetylene gives ethane...

Addition of `H_2` to acetylene gives ethane in présence of palladium but if `BaSO_4` and quinoline or sulphur are also added, the prodụct is ethene. Why?

Text Solution

Verified by Experts

.CH=CH+H_2 stackrelPdlongrarrarrow CH_pm=CH_2, stackrelH_2 / pdlongrarrarrow. Acetylene Ethene .CH_3-CH_x. Ethane Mixture of .BaSO_+. and quinoline/sulphur-poison the catalyst. Hence the efficiency of the catalyst decreases and the reaction stops at the first stage of reduction. Hence ethene is obtained.
Promotional Banner

Topper's Solved these Questions

  • SOLUTIONS

    V PUBLICATION|Exercise QUESTION BANK|158 Videos

  • THE d- AND f- BLOCK ELEMENTS

    V PUBLICATION|Exercise QUESTION BANK|190 Videos

Similar Questions

Explore conceptually related problems

2-Hexyne gives trans-2-hexene on treatment with Li / NH_3' Pd / BaSO_4' LiAlH _4' Pt / H_2'

Write the chemical equation of the electrolysis of water to which little sulphuric acid (H_2 SO_4) is added.

Why is it necessary to use acetic acid and not H_2SO_4 for acidification of sodium extract for testing sulphur using lead acetate test?

Take 25ml water in a beaker and pass electricity through it. The add little sulphuric acid in it. a) Why electricity didnot pass through pure water? b) What is your observation when H_2 SO_4 is added in water? c) Which type of ion formed more, when sulphuric acid is added in water.

Take 25 ml water in a beaker and the pass electricity through it. Then add little sulphuric acid in it: What happens when dil H_2SO_4 is added?

Paragraph Carboxylic acids are distinctly acidic because they ionize in water to give hydronium ions: RCOOH+H_(2)O hArr RCOO^(-) +H_(3)O^(+) The acidic strength depends upon the extent of ionizations of the acid and the stability of the anion formed. The acidic strength can also be expressed in terms of dissociation constant K_(a) or pK_(a) which are related as pK_(a)= -log K_(a) . Most unsubstituted carboxylic acids have K_(a) values in the range of 10^(-4) to 10^(-5) (pK_(a) =4-5) . The substitutents have marked effect on the acidic strength of carboxylic acids. Any group that stabilizes the carboxylate ion more than the carboxylic acid group will increase the acidic strength, and the group which destabilizes the carboxylate group more than the carboxylic acid group will decrease the acidic strength. In a similar manner, the electron-releasing groups makes benzoic acid weaker, while the electron-withdrawing groups make benzoic acid stronger. The ortho isomer of every substituted benzoic acid (whether electron releasing or electron withdrawing) is the strongest among the three isomers due to ortho effect. Which of the following is the weakest acid?

Paragraph Carboxylic acids are distinctly acidic because they ionize in water to give hydronium ions: RCOOH+H_(2)O hArr RCOO^(-) +H_(3)O^(+) The acidic strength depends upon the extent of ionizations of the acid and the stability of the anion formed. The acidic strength can also be expressed in terms of dissociation constant K_(a) or pK_(a) which are related as pK_(a)= -log K_(a) . Most unsubstituted carboxylic acids have K_(a) values in the range of 10^(-4) to 10^(-5) (pK_(a) =4-5) . The substitutents have marked effect on the acidic strength of carboxylic acids. Any group that stabilizes the carboxylate ion more than the carboxylic acid group will increase the acidic strength, and the group which destabilizes the carboxylate group more than the carboxylic acid group will decrease the acidic strength. In a similar manner, the electron-releasing groups makes benzoic acid weaker, while the electron-withdrawing groups make benzoic acid stronger. The ortho isomer of every substituted benzoic acid (whether electron releasing or electron withdrawing) is the strongest among the three isomers due to ortho effect. Which of the following statement is not correct?

A dark brown solid (X) reacts with NH_3 to form a mild explosive which decompuses to give a violet coloured gas(X)also reacts with H_2 to give an acid (Y). (Y) can also be prepared by heating its salt with H_3 PO_4 .X and Y are

V PUBLICATION-SURFACE CHEMISTRY-QUESTION BANK
  1. Physical adsorption is multimolecular while chemisorption is unimolecu...

    Text Solution

    |

  2. A colloidal sofution of 'AgI' is prepared by two different methods sho...

    Text Solution

    |

  3. Addition of H2 to acetylene gives ethane in présence of palladium but ...

    Text Solution

    |

  4. Explain the scientific reason behind the phenomena given below. Th...

    Text Solution

    |

  5. Adsorption of a gas on the surface of solid is generally accompanied b...

    Text Solution

    |

  6. In an adsorption experiment, a graph between log (x / m) versus log P ...

    Text Solution

    |

  7. Lyophilic colloịds are also called reversible sols. Why?

    Text Solution

    |

  8. Alum is used for cleaning muddy water. Give the reason?

    Text Solution

    |

  9. Smoke is passed through charged plates before it is allowed to come ou...

    Text Solution

    |

  10. Name two industrial processes in which heterogeneous catalysts are emp...

    Text Solution

    |

  11. Classify the fóllowing as multimolectilar, macromolecular and associat...

    Text Solution

    |

  12. Can you purity a sol by filtering it through an ordinary fiter paper?

    Text Solution

    |

  13. Peptization is the reverse of precipitation comment on the statement.

    Text Solution

    |

  14. Explain what obsserved i.when a beam of light is passed through a co...

    Text Solution

    |

  15. Justify the use of gelatin as a protective colloid.

    Text Solution

    |

  16. Explain the term (a) Flocculation value (b) Gold number

    Text Solution

    |

  17. What is the basis of artificial rain?

    Text Solution

    |

  18. The nature of bonding forces in adsorption are

    Text Solution

    |

  19. Which is not applicable to chemisorption? Its heat of adsorption is h...

    Text Solution

    |

  20. An emulsion is a colloidal system of : 2 solids, 2 liquids, one gas...

    Text Solution

    |