Which of the following is not correct?

White phosphorous reacts with thionyl chloride to form \(\mathrm{PCl}_3\) along with \(\mathrm{A}\) and \(\mathrm{B}\). \(\mathrm{A}\) and \(\mathrm{B}\) respectively are

A compound \(X\), of boron reacts with \(\mathrm{NH}_3\) on heating to give another compound \(Y\), which is called inorganic benzene. The compound \(X\) can be prepared by treating \(\mathrm{BF}_3\) with lithium aluminium hydride. The compounds \(X\) and \(Y\) are represented by the formulas.

Identify the reaction in which oxygen is not one of the products

One mole of \(\mathrm{C}_2 \mathrm{H}_5 \mathrm{OH}(l)\) was completely burnt in oxygen to form \(\mathrm{CO}_2(\mathrm{~g})\) and \(\mathrm{H}_2 \mathrm{O}(l)\). The standard enthalpy of formation \(\left(\Delta_f \mathrm{H}^{\ominus}\right)\) of \(\mathrm{C}_2 \mathrm{H}_5 \mathrm{OH}(l), \mathrm{CO}_2(\mathrm{~g})\) and \(\mathrm{H}_2 \mathrm{O}(l)\) is \(x, y, z \mathrm{~kJ} \mathrm{~mol}^{-1}\) respectively. What is \(\Delta_r \mathrm{H}^{\ominus}\) (in \(\mathrm{kJ} \mathrm{mol}^{-1}\) ) for this reaction?

The formation of oxide ion \(\mathrm{O}^{2-}\) from oxygen atom requires an exothermic reaction, followed by an endothermic step as shown below. The process of formation of \(\mathrm{O}^{2-}\) in gas phase is unfavorable \(\left(\Delta H^{\ominus}=+\right.\) ve \()\), even though it has stable configuration of the nearest noble gas neon. This is because
\(\begin{aligned} & \mathrm{O}(g)+e^{-} \longrightarrow \mathrm{O}^{-}(g) ; \Delta H^{\ominus}=-141 \mathrm{~kJ} \mathrm{~mol}^{-1} \\ & \mathrm{O}^{-}(g)+e^{-} \longrightarrow \mathrm{O}^{2-}(g) ; \Delta H^{\ominus}=+760 \mathrm{~kJ} \mathrm{~mol}^{-1}\end{aligned}\)

The standard reduction potentials of \(2 \mathrm{H}^{+} / \mathrm{H}_2, \mathrm{Cu}^{2+} / \mathrm{Cu}\), \(\mathrm{Zn}^{2+} / \mathrm{Zn}\) and \(\mathrm{NO}_3^{-}, \mathrm{H}^{+} / \mathrm{NO}\) are \(0.0,0.34,-0.76\) and 0.97 V pespectively. Identify the correct statements from the following
I. \(\mathrm{H}^{+}\)does not oxidize Cu to \(\mathrm{Cu}^{2+}\)
II. Zn reduces \(\mathrm{Cn}^{2+}\) to Cu
III. \(\mathrm{NO}_3^{-}\)oxidizes Cu to \(\mathrm{Cu}^{2+}\)

The angle between the pair of straight lines formed by joining the points of intersection of \(x^2+y^2=4\) and \(y=3 x+c\) to the origin is a right angle. Then \(c^2\) is equal to

Let \(\vec{a}=2 \hat{i}+\hat{j}-\hat{k}\) and \(\vec{b}=\hat{i}+3 \hat{j}-5 \hat{k}\) be two vectors, and \(\overrightarrow{\mathrm{r}}\) be a vector along the vector \(3 \overrightarrow{\mathrm{a}}-2 \overrightarrow{\mathrm{b}}\) such that \(|\overrightarrow{\mathrm{r}}|=\sqrt{74}\). If the direction of \(\vec{r}\) is opposite to that of \(3 \vec{a}-2 \vec{b}\), then \(\overrightarrow{\mathrm{r}}=\)

A wire of length \(L\) has a charge \(Q\) distributed uniformly along its length. The wire is bent in the shape of a semicircle. The magnitude of the electric field at the centre of curvature of the semicircle is

The rate constant is same for $3$ reactions of order $\mathrm{I}$, $\mathrm{II}$ and $\mathrm{III}$, respectively, the unit of concentration being in moles per litre. If the concentration of the reactant is unity, the rates of reaction ${\mathrm{R}}_1, {\mathrm{R}}_2, {\mathrm{R}}_3$ will be

A small source of sound vibrating at a frequency \(500 \mathrm{~Hz}\) is rotated along a circle of radius \(\frac{100}{\pi} \mathrm{cm}\) at a constant angular speed of 5 revolutions per second. The minimum and maximum frequency of the sound observed by a listener situation in the plane of the circle is (speed of sound is \(332 \mathrm{~ms}^{-1}\) )

A beam of light both reflects and refracts at the surface between air and glass. The index of refraction of the glass is 1.4. If the refracted and the reflected rays are perpendicular to each other, then the angle of incidence in the air is