19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
On hydroloysis, diborane produces
Boric acid has a polymeric layer structure in which planar BO3 units are joined by
Boric acid is prepared from borax by the action of :
An aqueous solution of boric acid is found to be weakly acidic in nature. This acidic character arises due to the following reasons.
H3BO3 is:
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:
What happens when a mixture of cobalt oxide and borax is heated in a flame on a loop of platinum wire ?
Borax bead test is responded by:
The number of OH units directly linked to boron atoms in Na2B4O7.10H2O is:
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:
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) = = =
On the addition of mineral acid to an aqueous solution of borax, the following compound is formed:
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…
Which of the following compounds are formed when BCl3 is treated with water ?
Which of the following is the electron deficient molecule ?
Which is the hardest compound of boron ?
The exhibition of highest co-ordination number depends on the availability of vacant orbitals in the central atom. Which of the following elements is not likely to act as central atom in MF - ?
Which of the following does not show similarity between boron and aluminium ?
When aluminium hydroxide dissolves in NaOH solution, the product is:
The main factor responsible for weak acidic nature of B—F bonds in BF3 is:
Which of the following compounds are formed when boron trichloride is treated with water?
Boron is unable to form BF - ions due to
The element which exists in liquid state for a wide range of temperature and can be used for measuring high temperature is
Which of the following oxides is acidic in nature ?
Assertion : Boron always forms covalent bond. Reason : The small size of B3+ favours formation of co- valent bond.