The total number of coordination sites in ethylenedi aminetetraacetate \((EDTA^ {4 -})\) is

Molal depression constant for a solvent is \(4.0\, K\, Kg\, mol^{-1}\). The depression in the freezing point of the solvent for \(0.03\, mol\, kg^{-1}\) solution of \(K_2SO_4\) is .............. \(\mathrm{K}\) (Assume complete dissociation of the electrolyte)

The reaction of ozone with oxygen atoms in the presence of chlorine atoms can occur by a two step process shown below \({O_3}(g)\, + \,C{l^ * }(g)\, \to \,{O_2}(g) + Cl{O^ * }(g)\) ..... \((i)\)               \([{K_i} = 5.2 \times {10^9}\,\,L\,mo{l^{ - 1}}\,{s^{ - 1}}]\) \(Cl{O^ * }(g) + {O^ * }(g)\, \to \,{O_2}(g) + \,C{l^ * }(g)\) ..... \((ii)\)                \([{K_{ii}} = 2.6 \times {10^{10}}\,\,L\,mo{l^{ - 1}}\,{s^{ - 1}}]\) The closest rate constant for the overall reaction  \({O_3}(g){\mkern 1mu}  + {\mkern 1mu} {O^*}(g){\mkern 1mu}  \to {\mkern 1mu} 2{O_2}(g)\) is  ........... \(L\,\,mo{l^{ - 1}}\,{s^{ - 1}}\)

A sample of \(0.125\,g\) of an organic compound when analysed by Duma's method yields \(22.78\,mL\) of nitrogen gas collected over \(KOH\) solution at \(280\,K\) and \(759\,mm\,Hg\). The percentage of nitrogen in the given organic compound is.(Nearest integer). \((a)\) The vapour pressure of water at \(280 K\) is \(14.2\) \(mm Hg\) \((b)\) \(R =0.082 L\) atm \(K ^{-1} mol ^{-1}\)

The correct statement amongst the following is :

Choose the halogen which is most reactive towards \(SN1\) reaction in the given compounds \((A, B, C , D)\)

The reaction \(2N_2O_5\,(g) \to  4NO_2\,(g) + O_2\,(g)\) follows first order kinetics. The pressure of a vessel containing only \(N_2O_5\) was found to increase from \(50\,mmHg\) to \(87 .5\,mmHg\) in \(30\,min.\) The pressure exerted by the gases after \(60\,min.\) will be .......... \(mmHg\) (assume temperature remains constant)

Treatment of phenol with chloroform in the presence of sodium hydroxide, which further results in _______ than water splitting in the presence of acid.

Let \( S=\{(m,n): m, n\in\{1,2,3,.....,50\}\} \). If the number of elements (m, n) in S such that \( 6^{m}+9^{n} \) is a multiple of 5 is p and the number of elements (m, n) in S such that \( m+n \) is a square of a prime number is q, then \( p+q \) is equal to :

A double convex lens has power \(P\) and same radii of curvature \(R\) of both the surfaces. The radius of curvature of a surface of a plano-convex lens made of the same material with power \(1.5P\) is ......\(R\)

If the angular momentum of a planet of mass \(m\), moving a round the Sun in a circular orbit its \(L\), about the center of the Sun, its areal velocity is

\(1\) Faraday electricity was passed through \(\mathrm{Cu}^{2+}(1.5\) \(\mathrm{M}, 1 \mathrm{~L}) / \mathrm{Cu}\) and \(0.1\) Faraday was passed through \(\mathrm{Ag}^{+}(0.2 \mathrm{M}, 1 \mathrm{~L}) / \mathrm{Ag}\) electrolytic cells. After this the two cells were connected as shown below to make an electrochemical cell. The emf of the cell thus formed at 298 K is-

Given: \(\mathrm{E}_{\mathrm{Cu}^{2+} / \mathrm{Cu}}^{\mathrm{o}}=0.34 \mathrm{~V}\)
\(\mathrm{E}_{\mathrm{Ag}^{+} / \mathrm{Ag}}^0=0.8 \mathrm{~V}\)
\(\frac{2.303 \mathrm{RT}}{\mathrm{F}}=0.06 \mathrm{~V}\)

Arrange the following compounds in increasing order of rate of aromatic electrophilic substitution reaction