19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Which of the following compounds are formed when BCl3 is treated with water ?
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 [B(OH)4]– and the geometry of the complex a…
On the addition of mineral acid to an aqueous solution of borax, the following compound is formed:
Na B O .10H O X Y Z D D ¾¾® ¾¾® + X, Y and Z in the reaction are (a) X Na B O , Y NaBO , Z B O = = = (b) X Na B O , Y B O , Z H BO = = = (c) X B O , Y NaBO , Z B(OH) = = = (d) X NaBO , Y B O , Z B(OH) = = =
Na B O .10H O Na B O X NaBO B O Y z D ¾¾® ¯ D + 39. (S) Borax is used as a cleansing agent because on dissolv- ing in water, it gives:
The number of OH units directly linked to boron atoms in Na2B4O7.10H2O is:
Borax bead test is responded by:
What happens when a mixture of cobalt oxide and borax is heated in a flame on a loop of platinum wire ?
Boric acid H3BO3 and BF3 have the same number of elec- trons. The former is a solid and the latter is a gas. The reason is:
H3BO3 is:
An aqueous solution of boric acid is found to be weakly acidic in nature. This acidic character arises due to the following reasons.
Boric acid is prepared from borax by the action of :
Boric acid has a polymeric layer structure in which planar BO3 units are joined by
On hydroloysis, diborane produces
In diborane,
The type of hybridization of boron in diborane is
In diborane, the two H – B – H angles are nearly :
The structure of diborane (B2H6) contains :
In B2H6:
Na B O X H BO . + ® What is X in the reaction ?
When strongly heated, orthoboric acid leaves a residue of:
o o Re d hot 100 C 160 C H BO X Y B O ; ¾¾¾® ¾¾¾® ¾¾¾® X and Y respectively are:
From B2H6, all the following can be prepared except:
A mixture of boron trichloride and hydrogen is subjected to silent electric discharge to form ‘A’ and HCl. ‘A’ is mixed with NH3 and heated to 200oC to form ‘B’. The formula of ‘B’ is:
Diborane reacts with ammonia under different conditions to give a variety of products. Which one among the following is not fomed in these conditions?