Vitamin B12 is a coordination compound of _______

What is the order of hydrolysis of methyl acetate in acidic medium?

\(\Lambda_m^{\circ}\) values for electrolytes \(AB , HB\) and AD are \(120.5,300.9\) and \(80.0 S cm ^2 mol^{-1}\) respectively.
\(\Lambda_m^{\circ}\) value for HD is:

Aldol condensation reaction is not given by :

Nitration of aniline with nitric acid and sulphuric acid gives major product as

Read the passage carefully and answer the following questions
There are mainly four series of the transition metals, \(3 d\) series ( \(S c\) to Zn), \(4 d\) series (Y to Cd), \(5 d\) series ( La and Hf to Hg ) and 6d series which has \(A c\) and elements from \(R f\) to \(C n\). The two series of the inner transition metals; \(4 f\) (Ce to Lu) and \(5 f\) (Th to Lr) are known as lanthanoids and actinoids respectively. Their chemical properties are transitional between those of \(s\) and \(p\)-block elements. The transition metals (with the exception of Zn, Cd and Hg) are very hard and have low volatility. Their melting and boiling points are high. Transition metals have incomplete d subshell either in neutral atom or in their ions. With partly filled d orbitals these elements exhibit certain characteristic properties such as display of a variety of oxidation states, formation of coloured ions and entering into complex formation with a variety of ligands. The transition metals and their compounds are known for their catalytic activity.
The highest oxidation states shown by V , Fe and Ni respectively are __________ .

The value of conductivity of some selected materials at 298.15 K is given below. From the value
identify a semiconductor.

The area (in sq.units) of the region bounded by the curves \(y = x\) and y = \(x^3\) is:

Match List-I with List-II

List-I (Physical Quantity)	List-II (Units)
(A) Magnetic field	(I) \( J \, T^{-1} \)
(B) Magnetic moment	(II) \( T \, m \, A^{-1} \)
(C) Pole strength	(III) \( J \, T^{-1} m^{-1} \)
(D) Permeability of free space	(IV) \( Wb \, m^{-2} \)

Choose the correct answer from the options given below:

In angiosperms, the outer wall of ovary develops into :

In the given circuit, \( R_1 = 6 \Omega \), \( R_2 = 3 \Omega \), \( C_1 = 4 \mu F \) and \( C_2 = 5 \mu F \). When key K is closed, the charge stored in \( C_1 \) is

Arrange the following events in correct sequence :
(A) Virus infects macrophages
(B) Viral DNA is produced by reverse transcriptase
(C) Viral DNA incorporates into host genome
(D) Viral RNA is introduced into macrophages
(E) New viruses are produced
Choose the correct answer from the options given below :

The synthesis of alkyl fluoride is best achieved through