The Gattermann-Koch reaction is used in the industrial preparation of benzaldehyde.
The electrophile involved in this reaction is:

Choose the correct statements from the following :
(A) two different solutions of sucrose of same molality prepared in different solventswill have the same depression in freezing point.
(B) the osmotic pressure of a solution is given by the equation \(II = CRT\) (where C is the molarity of the solution)
(C) decreasing order of osmotic pressure for 0.01 M aqueous solution of \(BaCl _2, KCl , CH _3 COOH\), and sucrose is \(BaCl _2 > KCl > CH _3 COOH >\) sucrose
(D) according to Raoult's law the vapor pressure exerted by a volatile component of asolution is directly proportional to its mole fraction in the solution
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\(Mn_2O_7\), \(CrO\) and \(V_2O_5\) respectively are:

Identify the most volatile compound

The limiting molar conductivities for \(NaCl\), \(HCl\) and \(CH_3COONa\) are \(126.4\), \(425.9\) and \(91.0\ S\ cm^2\ mol^{-1}\), respectively. Calculate the limiting molar conductivity for acetic acid.

Which among the following are coordination complexes?
(A) Mohr's salt
(B) Tetraamminediaquacobalt (II) ion
(C) Carnallite
(D) Potassium ferricyanide
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Answer the question on basis of passage given below :
Vitamins represent a group of organic compounds which are needed in small amount for the healthy growth and maintenance of our body. These are not synthesized by the body and are supplied in the diet. The deficiency of vitamins can be supplemented with medicines. Which vitamins are water soluble ?

The \(K H\) values of \(HCOOH > CH _4> Ar\) and CO _2 > at \(2 9 8 K\) are \(1 . 8 3 \times 1 0 - 5 ~ k b a r\), \(0.413 kbar , 40 kbar\) and 1.67 kbar respectively. Arrange them in the order of their decreasing solubility at constant pressure :

Mr. Vishnu has an initial investment of Rs. 80,000 in an investment plan. After 3 years, it has grown to Rs. \(1,00,000\), then his rate of return is

The principal value of \(\operatorname{cosec}^{-1} \left(\frac{2}{\sqrt{3}}\right)\) is:

An inductor of reactance 100 \( \Omega \) and resistor of resistance 100 \( \Omega \) are joined in series and connected by AC source of emf 220 V. Power dissipated in the circuit is:

The waves used by artifical satellite for communication purposes are

Answer the question on the basis of passage given below:
In the periodic table, the d-block contains the elements of group \(3\) to \(12\). The d-orbitals are progressively filled in each of the four long periods. The elements of d block referred as transition metals have partly filled d orbitals and exhibit certain characteristic properties such as variety of oxidation states, formation of coloured ions, act as catalyst and show paramagnetic behaviour.
The two inner transition metals series \(4f\) and \(5f\) are known as Lanthanoids and Actinoids respectively. The lanthanoids resemble one another more closely as compared to ordinary transition elements in any series.
For the four successive transition elements given below, the stability of +2 oxidation state will be:
A. \(\operatorname{Cr}( Z =24)\)
B. \(Mn ( Z =25)\)
C. \(Fe ( Z =26)\)
D. \(Co ( Z =27)\)
Choose the correct answer from the options given below: