Reaction of BeO with ammonia and hydrogen fluoride gives ' A ' which on thermal decomposition gives \(BeF _2\) and \(NH _4 F\). What is ' A '?

In \(\mathrm{SO}_2, \mathrm{NO}_2^{-}\)and \(\mathrm{N}_3^{-}\)the hybridizations at the central atom are respectively :

Which among the following has highest boiling point?

The number of species from the following in which the central atom uses \(\mathrm{sp}^3\) hybrid orbitals in its bonding is _______. [\(\mathrm{NH}_3, \mathrm{SO}_2, \mathrm{SiO}_2, \mathrm{BeCl}_2, \mathrm{CO}_2, \mathrm{H}_2 \mathrm{O}, \mathrm{CH}_4, \mathrm{BF}_3\)]

\(\mathrm{X} \mathrm{g}\) of ethylamine is subjected to reaction with \(\mathrm{NaNO}_2 / \mathrm{HCl}\) followed by water; evolved dinitrogen gas which occupied \(2.24 \mathrm{~L}\) volume at \(STP.\) \(\mathrm{X}\) is _______ \(\times 10^{-1} \mathrm{~g}\).

Complete reduction of benzene-diazonium chloride with \(Zn/HCl\) gives

Three moles of an ideal gas are compressed isothermally from \(60 \mathrm{~L}\) to \(20 \mathrm{~L}\) using constant pressure of \(5 \mathrm{~atm}\). Heat exchange \(Q\) for the compression is _______ Lit. atm.

The probability that a randomly chosen \(2 \times 2\) matrix with all the entries from the set of first \(10\) primes, is singular, is equal to

Consider a moving coil galvanomenter (MCG):
A. The torsional constant in moving coil galvanometer has dimentions \(\left[\mathrm{ML}^2 \mathrm{~T}^{-2}\right]\)
B. Increasing the current sensitivity may not necessarily increase the voltage sensitivity.
C. If we increase number of turns \((\mathrm{N})\) to its double \((2 \mathrm{~N})\), then the voltage sensitivity doubles.
D. MCG can be converted into an ammeter by introducing a shunt resistance of large value in parallel with galvanometer.
E. Current sensitivity of MCG depends inversely on number of turns of coil.
Choose the correct answer from the options given below:

A block is fastened to a horizontal spring. The block is pulled to a distance \(x =10\,cm\) from its equilibrium position (at \(x =0\) ) on a frictionless surface from rest. The energy of the block at \(x =5\) \(cm\) is \(0.25\,J\). The spring constant of the spring is \(.........Nm ^{-1}\)

Let a complex number \(z ,| z | \neq 1\), satisfy \(\log _{\frac{1}{\sqrt{2}}}\left(\frac{| z |+11}{(| z |-1)^{2}}\right) \leq 2 .\) Then, the largest value of \(|z|\) is equal to ............

Total number of tripeptides possible by mixing of valine and proline is \(............\).

Let \(\vec{a}\) and \(\overrightarrow{ b }\) be two non-zero vectors perpendicular to each other and \(|\overrightarrow{ a }|=|\overrightarrow{ b }| .\) If \(|\overrightarrow{ a } \times \overrightarrow{ b }|=|\overrightarrow{ a }|,\) then the angle between the vectors \((\vec{a}+\vec{b}+(\vec{a} \times \vec{b}))\) and \(\vec{a}\) is equal to