हिंदी
कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान कक्षा ११

Identify the compounds A, X and Z in the following reactions: X→370KΔHBOX2→>370KΔZ

Advertisements
Advertisements

प्रश्न

Identify the compounds A, X and Z in the following reactions:

\[\ce{X ->[Δ][370 K] HBO2 ->[Δ][> 370 K] Z}\]

टिप्पणी लिखिए
Advertisements

उत्तर

\[\ce{\underset{(X)}{H3BO3} ->[Δ, 370 K] \underset{Metaboric acid}{HBO2} + H2O}\]

\[\ce{4HBO2 ->[Δ, 370 K][-H2O] \underset{Tetraboric acid}{[H2B4O7]} ->[Read heat] \underset{Boric trioxide (Z)}{2B2O3} + H2O}\]

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 11: The p-block Elements - Multiple Choice Questions (Type - I) [पृष्ठ १३९]

APPEARS IN

एनसीईआरटी एक्झांप्लर Chemistry Exemplar [English] Class 11
अध्याय 11 The p-block Elements
Multiple Choice Questions (Type - I) | Q 34.(ii) | पृष्ठ १३९

संबंधित प्रश्न

Suggest reasons why the B–F bond lengths in BF3 (130 pm) and `"BF"_4^(-)` (143 pm) differ.


What happens when BF3 is reacted with ammonia?


In some of the reactions thallium resembles aluminium, whereas in others it resembles with group I metals. Support this statement by giving some evidences.


What do you understand by inert pair effect?


Write a balanced equation for B2H6 + NH3 → ?


The geometry of a complex species can be understood from the knowledge of type of hybridisation of orbitals of central atom. The hybridisation of orbitals of central atom in [Be(OH)4] and the geometry of the complex are respectively.


Which of the following oxides is acidic in nature?


Ionisation enthalpy (∆iH1kJ mol–1) for the elements of Group 13 follows the order.


A compound X, of boron reacts with NH3 on heating to give another compound Y which is called inorganic benzene. The compound X can be prepared by treating BF3 with Lithium aluminium hydride. The compounds X and Y are represented by the formulas.


Which of the following statements are correct. Answer on the basis of Figure.

(i) The two birdged hydrogen atoms and the two boron atoms lie in one plane;

(ii) Out of six B – H bonds two bonds can be described in terms of 3 centre 2-electron bonds.

(iii) Out of six B – H bonds four B – H bonds can be described in terms of 3 centre 2 electron bonds;

(iv) The four-terminal B – H bonds are two centre-two electron regular bonds.


Aluminium dissolves in mineral acids and aqueous alkalies and thus shows amphoteric character. A piece of aluminium foil is treated with dilute hydrochloric acid or dilute sodium hydroxide solution in a test tube and on bringing a burning matchstick near the mouth of the test tube, a pop sound indicates the evolution of hydrogen gas. The same activity when performed with concentrated nitric acid, reaction doesn’t proceed. Explain the reason.


Explain the following:

PbX2 is more stable than PbX4.


Explain the following:

Electron gain enthalpy of chlorine is more negative as compared to fluorine.


Match the species given in Column I with properties given in Column II.

Column I Column II
(i) Diborane (a) Used as a flux for soldering metals
(ii) Galluim (b) Crystalline form of silica
(iii) Borax (c) Banana bonds
(iv) Aluminosilicate (d) Low melting, high boiling, useful for measuring high temperatures
(v) Quartz (e) Used as catalyst in petrochemical industries

Account for the following observations:

Though fluorine is more electronegative than chlorine yet BF3 is a weaker Lewis acid than BCl3 


Three pairs of compounds are given below. Identify that compound in each of the pairs which has group 13 element in more stable oxidation state. Give reason for your choice. State the nature of bonding also.

TlCl3, TlCl


A nonmetallic element of group 13, used in making bullet proof vests is extremely hard solid of black colour. It can exist in many allotropic forms and has unusually high melting point. Its trifluoride acts as Lewis acid towards ammonia. The element exihibits maximum covalency of four. Identify the element and write the reaction of its trifluoride with ammonia. Explain why does the trifluoride act as a Lewis acid.


Which one of the following is the correct statement?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×