Hardest compound of boron is
magnesium boride
aluminium boride
boron nitride
boron carbide
D.
boron carbide
Boron carbide is written as B4C. It is produced by reducing B2O3 with C at 1600° C. Fibres of B4C have an enormous tensile strength and are used to make bullet-proof clothing.
Rate determining step in nitration of benzene is
formation of NO2+
formation of carbocation
replacement of H atom
none of these.
The aqueous solution of which of the following salt will have the lowest pH ?
NaClO3
NaClO
NaClO4
NaClO2
Which ofthe following alkanes is optically active?
3-Methylhexane
Propane
2, 3, 4-Trimethylpentane
2-Methylbutane
Assertion : Na2SO4 is soluble in water while BaSO4 is not.
Reason : Lattice energy of BaSO4 exceeds its hydration energy.
If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
If Assertion is true but Reason is false.
If Assertion is false but Reason is true.