Copper matte is composed of ____

Number of completely filled orbitals in xenon atom \((\mathrm{Xe})\) is

Which of the following are disproportionation reactions?
\((\mathrm{g}=\sigma, l=(ద, \mathrm{aq}=\text { జe, } \mathrm{s}=\text { ఘ) }\)
(A) \(2 \mathrm{NO}_{2(\mathrm{~g})}+2 \mathrm{NaOH}_{(\mathrm{aq})} \rightarrow \mathrm{NaNO}_{2(\mathrm{aq})}+\mathrm{NaNO}_{3(\mathrm{aq})}+\mathrm{H}_2 \mathrm{O}_{(l)}\)
(B) \(\mathrm{Cl}_{2(\mathrm{~g})}+2 \mathrm{NaOH}_{(\mathrm{aq})} \rightarrow \mathrm{NaClO}_{(\mathrm{aq})}+\mathrm{NaCl}_{(\mathrm{aq})}+\mathrm{H}_2 \mathrm{O}_{(\mathrm{l})}\)
(C) \(3 \mathrm{ClO}^{-} \rightarrow 2 \mathrm{Cl}^{-}+\mathrm{ClO}_3^{-}\)
(D) \(3 \mathrm{Mg}_{(\mathrm{s})}+\mathrm{N}_{2(\mathrm{~g})} \rightarrow \mathrm{Mg}_3 \mathrm{~N}_{2(\mathrm{~s})}\)

The measured osmotic pressure of a solution prepared by dissolving \(17.4 \mathrm{mg}\) of \(\mathrm{K}_2 \mathrm{SO}_4\) in \(2 \mathrm{~L}\) of water at \(27^{\circ} \mathrm{C}\) is \(3.735 \times 10^{-3}\) bar.
The van't Hoff factor is
\(\left(R=0.083 \mathrm{~L} \mathrm{bar} \mathrm{K}^{-1} \mathrm{~mol}^{-1}\right.\); atomic weights
\(\mathrm{K}=39, \mathrm{~S}=32 ; \mathrm{O}=16\) )

The correct order of reactivity of the following compounds, towards electrophilic substitution reactions is

\(50 \mathrm{~mL}\) of \(\mathrm{H}_2 \mathrm{O}\) is added to \(50 \mathrm{~mL}\) of \(1 \times 10^{-3} \mathrm{M}\) barium hydroxide solution. What is the \(\mathrm{pH}\) of the resulting solution?

Which of the following reactions is not correct?

In how many ways one can send 6 new-year greeting cards to 4 people?

If \(a=\frac{1-i \sqrt{3}}{2}\), then the correct matching of 'List-I from List-II is
List-I
List-II
(i) \(a \bar{a}\)
(A) \(-\frac{\pi}{3}\)
(ii) \(\arg \left(\frac{1}{\bar{a}}\right)\)
(B) \(-i \sqrt{3}\)
(iii) \(a-\bar{a}\)
(C) \(2 i / \sqrt{3}\)
(iv) \(\operatorname{Im}\left(\frac{4}{3 a}\right)\)
(D) 1
(E) \(\pi / 3\)
(F) \(\frac{2}{\sqrt{3}}\)
correct match is
(i)
(ii)
(iii)
(iv)

Consider the following gaseous equilibrium reactions (I), (II) and (III) with equilibrium constants \(\mathrm{K}_1, \mathrm{~K}_2\) and \(\mathrm{K}_3\) respectively
I) \(\frac{1}{2} \mathrm{~N}_2+\frac{3}{2} \mathrm{H}_2 \rightleftharpoons \mathrm{NH}_3\)
II) \(2 \mathrm{NO} \rightleftharpoons \mathrm{N}_2+\mathrm{O}_2\)
III) \(\mathrm{H}_2+\frac{1}{2} \mathrm{O}_2 \rightleftharpoons \mathrm{H}_2 \mathrm{O}\)
The correct expression for the equilibrium constant for the gaseous equilibrium reaction \(2 \mathrm{NH}_3+\frac{5}{2} \mathrm{O}_2 \rightleftharpoons 2 \mathrm{NO}+3 \mathrm{H}_2 \mathrm{O}\) is

If \(\operatorname{Tanh}^{-1} \mathrm{x}=\operatorname{Coth}^{-1} \mathrm{y}=\log \sqrt{5}\), then \(\operatorname{Tan}^{-1}(\mathrm{xy})=\)

The number of circles that touch all the three lines \(x+y-1=0, x-y-1=0\) and \(y+1=0\) is

If the time taken for a radioactive substance to decay \(8 \%\) to \(77 \%\) is 12 minutes, then the half life of the substance in minutes is