For \(OF _2\) molecule consider the following: \((A)\) Number of lone pairs on oxygen is 2 . \((B)\) \(FOF\) angle is less than \(104.5^{\circ}\). \((C)\) Oxidation state of \(O\) is \(-2\). \((D)\) Molecule is bent ' \(V\) ' shaped. \((E)\) Molecular geometry is linear. Correct options are:

Solid \(Ba(NO_3)_2\) is gradually dissolved in a \(1.0 \times 10^{-4}\, M\, Na_2CO_3\) solution. At which concentration of \(Ba^{2+}\), precipitate of \(BaCO_3\) begins to form ? \((K_{sp}\) for \(BaCO_3 = 5.1 \times 10^{-9})\)

The primary and secondary valencies of cobalt respectively in \(\left[ Co \left( NH _3\right)_5 Cl \right] Cl _2\) are :

In following pairs, the one in which both transition metal ions are colourless is

During the nuclear explosion, one of the products is \(^{90}  \mathrm{Sr}\) with half life of \(6.93\) years. if \(1 \;\mu g\) of \(^{90} \mathrm{Sr}\) was absorbed in the bones of a newly born baby in place of \(Ca\), how much time, in years, is required to reduce it by \(90 \%\) if it is not lost metabolically

Given below are two statements: Statements \(I\) : \(SbCI _5\) is more covalent than \(SbCI _3\) Statements \(II\): The higher oxides of halogens also tend to be more stable than the lower ones. In the light of the above statements, choose the most appropriate answer from the options given below

For the following reactions \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{Br}+\mathrm{Z}^{-}\)\(\xrightarrow[{{\text{Sublimation}}}]{{{k_s}}} \mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{Z}+\mathrm{Br}^{-}\) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{Br}+\mathrm{Z}^{-}\)\(\xrightarrow[{{\text{elimination}}}]{{{k_e}}}\mathrm{CH}_{3} \mathrm{CH}= \mathrm{CH}_{2} +\mathrm{HZ}+\mathrm{Br}^{-}\) where  \(\mathrm{Z}^{-}=\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{O}^{-}(\mathrm{A})\) or \(\begin{array}{*{20}{c}}
  {\,C{H_3}} \\ 
  {|\,\,\,\,\,} \\ 
  {C{H_3} - C - {O^ - }(B)} \\ 
  {|\,\,\,\,} \\ 
  {\,\,C{H_3}} 
\end{array}\) \(\mathrm{k}_{\mathrm{s}}\) and \(\mathrm{k}_{\mathrm{e}},\) are \(,\) respectively, the rate constants for the substitution and elimination, and \(\mu=\frac{\mathrm{k}_{\mathrm{s}}}{\mathrm{k}_{\mathrm{e}}},\) the correct options is

Given below are two statements :
Statement I : Piciric acid is 2,4,6 - trinitrotoluene.
Statement II : Phenol - 2,4 - disulphonic acid is treated with Conc. \(HNO _3\) to get picric acid.
In the light of the above statements, choose the most appropriate answer from the options given below :

The decay of a proton to neutron is :

A gas mixture consists of \(3\) moles of oxygen and \(5\) moles of argon at temperature \(T\). Assuming the gases to be ideal and the oxygen bond to be rigid, the total internal energy (in units of \(RT\) ) of the mixture is

What is the conductivity of a semiconductor sample having electron concentration of \(5 \times 10^{18}\, m^{-3}\), hole concentration of \(5 \times  10^{19}\, m^{-3}\), electron mobility of \(2 .0\, m^2\, v^{-1}\, s^{-1}\) and hole mobility of \(0.01\, m^2\, v^{ -1}\, s^{-1}\) ?........\({\left( {\Omega  - m} \right)^{ - 1}}\) (Take charge of electron as \(1.6 \times 10^{-19}\, C\))

\(0.3\,g\) of ethane undergoes combustion at \(27^{\circ}\,C\) in a bomb calorimeter. The temperature of calorimeter system (including the water) is found to rise by \(0.5^{\circ}\,C\). The heat evolved during combustion of ethane at constant pressure is \(.......kJ\,mol { }^{-1}\). (Nearest integer) [Given : The heat capacity of the calorimeter system is \(20\, kJ\, K ^{-1}, R =8.3\, JK ^{-1}\, mol ^{-1}\). Assume ideal gas behaviour. Atomic mass of \(C\) and \(H\) are \(12\) and \(1\, g\, mol ^{-1}\) respectively]

The density and breaking stress of a wire are \(6 \times\) \(10^4 \mathrm{~kg} / \mathrm{m}^3\) and \(1.2 \times 10^8 \mathrm{~N} / \mathrm{m}^2\) respectively. The wire is suspended from a rigid support on a planet where acceleration due to gravity is \(\frac{1^{\text {rd }}}{3}\) of the value on the surface of earth. The maximum length of the wire with breaking is _______ \(\mathrm{m}\) (take, \(\mathrm{g}=\) \(\left.10 \mathrm{~m} / \mathrm{s}^2\right)\)