19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Alumina may be converted into anhydrous aluminium chloride by:
Moderate electrical conductivity is shown by
Which one of the following is not the characteristic property of carbon ?
When excesss of carbon dioxide is passed through lime water, the milkiness first formed disappears due to
Carbon and silicon belong to (IV) group. The maximum coordination number of carbon in commonly occurring compounds is 4, whereas that of silicon is 6. This is due to (AIPMT 1994)
Aluminium vessels should not be washed with materials containing washing soda since :
Complex formation is more likely to be possible in _____
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:
In the structure of diborane
Reactivity of borazole is higher than that of benzene because:
Boron nitride can be represented by the given structure. The structure of BN is similar to
The hardest compound of boron is:
Which of the following is not true regarding the nature of halides of boron ?
Thermite is a mixture of iron oxide and
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:
Borax bead test is responded by:
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) = = =
An aqueous solution of boric acid is found to be weakly acidic in nature. This acidic character arises due to the following reasons.
The bonds present in borazole are:
Alumina is:
On the addition of mineral acid to an aqueous solution of borax, the following compound is formed:
When excess of NaOH solution is added in potash alum, the product is:
The element which exists in liquid state for a wide range of temperature and can be used for measuring high temperature is
The decreasing order of power of boron halides to act as Lewis acids is (a) BF BCl BBr > > (b) BBr BCl BF > > (c) BCl BF BBr > > (d) BCl BBr BF > >