chemistry xenon hexafluoride reacts with silica to form a xenon compound the oxidation state of...

Download Chemistry Xenon hexafluoride reacts with silica to form a xenon compound The oxidation state of xenon

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  • Chemistry

    Single correct answer type:

    1. Which one of the following species is paramagnetic in nature?

    (A)

    (B)

    (C)

    (D)

    Solution: (D)

    The number of unpaired electrons and electronic configuration of the given species is

    shown below

    ( ) [ ] [ ]

    No. of unpaired electron

    ( ) [ ] [ ]

    No. of unpaired electron

    ( ) [ ] [ ]

    No. of unpaired electron

    ( ) [ ] [ ]

    Number of unpaired electrons

    The correct option among the following is ( )

    2. Given that, for the reaction,

    ( ) ⁄

    ( ) ⁄

    ( ) ⁄

    The bond dissociation energy of is

    (A) ⁄

    (B) ⁄

    (C) ⁄

  • (D) ⁄

    Solution: (C)

    Given,

    In this reaction, one mole of is formed

    of the reaction will remain same,

    i.e., ⁄

    Let the bond dissociation energy of bond be

    For the given reaction,

    ( ) ( )

    ( )

    ( )

    3. The pair of structures given below represents

    (A) Chain isomers

    (B) Position isomers

    (C) Tautomers

    (D) Metamers

    Solution: (B)

    The pair of the given

    represents position isomers. In case of position isomers, the difference lies in the

    position of substituent groups or atom in the same chain.

  • 4. In the extraction of copper from its sulphide ore, the metal is formed by the reduction

    of with

    (A)

    (B)

    (C)

    (D)

    Solution: (C)

    In the extraction of copper from its sulphide ore, the metal is formed by the reduction of

    with This reaction completes with the process of auto-reduction. Chemical

    reaction occurring in this reaction is as follows

    The molten copper is allowed to cool. During cooling, dissolved comes out in the

    form of blisters, so it is called blister copper.

    5. For the following reaction,

    ( ) ( ) ( ) ( ) at

    Then, for this equilibrium is

    (A)

    (B)

    (C)

    (D)

    Solution: (B)

    Given,

    For equilibrium, the Gibb’s free energy is calculated by using the formula.

    or,

  • 6. Xenon hexafluoride reacts with silica to form a xenon compound The oxidation

    state of xenon in is

    (A)

    (B)

    (C)

    (D)

    Solution: (C)

    Xenon hexa fluoride reacts with silica to form as

    The oxidation state of xenon in is as calculated below:

    Let the oxidation state of is

    ( ) ( )

    7. Neopentyl chloride reacts with benzene in presence of a Lewis acid ( ) to form

    (A)

    (B)

    (C)

    (D)

    Solution: (B)

  • 8. Lead is extracted from galena ( ) either by following ways.

    ( ) →

    ( ) →

    Auto-reduction process is

    (A) →

    (B) →

    (C) Both →

    and →

    (D) None of these

    Solution: (B)

    In auto-reduction, no external reducing agent is required. In such reduction reaction, the

    product formed acts as a reducing agent and reduces the oxide to metal. Thus, only

    reaction is called auto-reduction.

    ( ct as a reducing agent)

    9. In the reaction,

  • The major product formed is

    (A)

    (B)

    (C)

    (D)

    Solution: (C)

    The given reaction is an example of Perkin condensation. In this, reaction aromatic

    aldehydes react with acid anhydride of an aliphatic acid in presence of sodium salt of

    same acid to form unsaturated acid. The steps involved in the process are as

    follows

    Thus, the correct option is (C).

    10. Which one of the following represents the correct structure of cellulose?

    (A) Branched, ( ) and ( ) glucose

    (B) Unbranched, ( ) glucose

    (C) Branched, ( ) glucose

    (D) Unbranched, ( ) glucose

    Solution: (D)

    Cellulose has a straight chain polysaccharide composed only of The

    glucose glucose. These glucose units are linked together by

    glycosidic linkage. The structure is shown below:

  • Structure of cellulose

    11. The correct formula for plaster of Paris is

    (A)

    (B)

    (C)

    (D)

    Solution: (C)

    Plaster of Paris (POP) is a hemihydrate of calcium sulphate. Its chemical formula is

    [ ( ) ]

    12. The value of for the reaction,

    is At a given time, the composition of reaction mixture is

    [ ] [ ] [ ] In which direction, the reaction will proceed?

    (A) Forward direction

    (B) Reverse direction

    (C) No net reaction occur

    (D) None of these

    Solution: (B)

    For the reaction, the reaction quotient is given by

    [ ][ ] [ ] ⁄

    Given that,

    [ ] [ ] [ ]

  • Then, ( )( )

    ( )

    As, so the reaction will proceed in the reverse direction.

    13. Which of the following chemicals are used to manufacture methyl isocyanate that

    caused "Bhopal tragedy"?

    ( ) Methylamine

    ( ) Phosgene

    ( ) Phosphine

    ( ) Dimethylamine

    (A) ( ) and ( )

    (B) ( ) and ( )

    (C) ( ) and ( )

    (D) ( ) and ( )

    Solution: (A)

    Methyl isocyanate ( ) is industrially prepared by the reaction of methyl amine

    and phosgene (carbonyl chloride).

    14. The correct order of ease of adsorption of the hydrated alkali metal ions on an ion

    exchange resin is

    (A)

    (B)

    (C)

    (D)

    Solution: (A)

    Ease of adsorption of the hydrated alkali metal ions on an ion exchange resin

    decreases as the size of the alkali metal ion increases. Since. the order of the size of

    the alkali metal ions is

  • Thus, the ease of adsorption follows the order

    15. Identify the major product that is obtained on treatment of ( ) with

    ⁄ is

    (A) ( )

    (B)

    (C)

    (D)

    Solution: (B)

    ccording to Saytzeff’s rule, dehydrohalogenation occur in such a way that the major

    product is more highly substituted product.

    ( )

    ( ajor)

    ( inor)

    16. Among the following, the non-aromatic heterocyclic compound is

    (A) Piperidine

    (B) Pyrrole

    (C) Furan

    (D) Pyridine

    Solution: (A)

    Pyridine is aromatic, since, it satisfies all the conditions of a compound to be aromatic

    (here, lone pair on atom is and used in delocalization).

    Pyrrole is also aromatic and here, lone pair on atom is used in delocalization.

  • Furan also follows Huckels rule and other conditions for a compound to be aromatic.

    Piperidine is non-aromatic because, in it rule is not followed and moreover, no

    delocalization of electron takes place.

    17. If ion is larger than ions and ion is larger than ion, which of the

    following will be stable salt in water?

    (A) Sodium chloride

    (B) Sodium sulphide

    (C) Magnesium sulphide

    (D) Magnesium chloride

    Solution: (C)

    Higher the lattice energy, lower the solubility and more stable the salt in water. Since,

    lattice energy varies directly with charge. Therefore, among the four combinations

    given, the lattice energy of is higher than those of and . Hence,

    is stable salt in water and least soluble salt.

    18.

    Product P is

    (A)

  • (B)

    (C)

    (D)

    Solution: (B)

    19. Which of the following is correct statement?

    (A) Aluminum dissolves in dilute mineral acids but is made passive by concentrated

    nitr