19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
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:
In BX3, B – X distance is shorter than what is expected theoretically because (X = F, Cl, Br, I)
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 > >
BF3 is used as catalyst in several industrial processes due to its:
Which one of the following statements regarding BF3 is not correct?
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:
Group 13 elements show +1 and +3 oxidation states. Relative stability of +3 oxidation state may be given as (a) Tl Ga Al B In + + + + + > > > > (b) B Al Ga In Tl + + + + + > > > > (c) Al Ga Tl In B + + + + + > > > > (…
The stability of +1 oxidation state increases in the se- quence:
Ionisation enthalpy i ( H kJ mol ) - D for the elements of Group 13 follows the order
Which of the following compounds is known as inor- ganic benzene?
Which of the following species is not stable? (NEET 2019)
Which of the following is incorrect statement? (NEET 2019)
The correct order of atomic radii in group 13 elements is (NEET 2018)
MF which one of the following elements is unable to form ion? (NEET 2018)
It is because of inability of ns2 electrons of the valence shell to participate in bonding that (NEET 2017)
The element Z = 114 has been discovered recently. It will belong to which of the following family/group and electronic configuration ? (NEET 2017)
Boric acid is an acid because its molecule (NEET 2016)
The tendency of BF3, BCl3 and BBr3 to behave as Lewis acid decreases in the sequence (AIPMT 2010)
Silica is soluble in (Haryana PMT 2009)