Assertion (A) White tin is an example of tetragonal system.Reasoning (R) For a tetragonal system \(a=b=c\) and \(\alpha=\beta=\gamma \neq 90^{\circ}\). The correct answer is

For a first order reaction at \(27^{\circ} \mathrm{C}\), the ratio of time required for \(75 \%\) completion to \(25 \%\) completion of reaction is

When acetylene is passed through red hot iron tube, compound \(X\) is formed. Which one of the following reactions will yield \(X\) as the major product?

In the reaction, if \(\mathrm{X}\) is the reagent and \(\mathrm{Y}\) is the product, which of the following is not feasible?
In the reaction, if \(\mathrm{X}\) is the reagent and \(\mathrm{Y}\) is the product, which of the following is not feasible?

Identify the initiation step \(/ \mathrm{s}(\mathrm{X})\) and termination \(\mathrm{step} / \mathrm{s}(\mathrm{Y})\) of free radical chlorination of \(\mathrm{CH}_4\) from the following.
a) \(\dot{\mathrm{C}}_3+\dot{\mathrm{C}} \mathrm{l} \rightarrow \mathrm{CH}_3-\mathrm{Cl}\)
b) \(\dot{\mathrm{Cl}}+\dot{\mathrm{C}} l \rightarrow \mathrm{Cl}-\mathrm{Cl}\)
c) \(\dot{\mathrm{C}}_3+\mathrm{Cl}_2 \rightarrow \mathrm{CH}_3-\mathrm{Cl}+\dot{\mathrm{Cl}}\)
d) \(\mathrm{Cl}_2 \rightarrow 2 \dot{\mathrm{Cl}}\)
e) \(\mathrm{CH}_4+\dot{\mathrm{Cl}} \rightarrow \dot{\mathrm{C}} \mathrm{H}_3+\mathrm{HCl}\)
f) \(\mathrm{CH}_3+\dot{\mathrm{C}}_3 \rightarrow \mathrm{CH}_3-\mathrm{CH}_3\)

In which of the following metals extraction, impurities are removed as slag?
i. Al \(\quad\) ii. Fe
iii. Cu \(\quad\) iv. Zn
The correct option is

Iron sulphide is heated in air to form \(A\) an oxide of sulphur. \(A\) is dissolved in water to give an acid. The basicity of this acid is

Identify the correct order of ionic radii of the given species.

If \(\cos ^3 80^{\circ}+\cos ^3 40^{\circ}-\cos ^3 20^{\circ}=\mathrm{k}\), then \(\frac{4 \mathrm{k}}{3}=\)

If \((a, b)\) is the midpoint of the chord \(2 x-y+3=0\) of the circle \(x^2+y^2+6 x-4 y+4=0\), then \(2 a+3 b=\)

While passing through the applied magnetic field, which of the following undergoes the maximum deflection?

If the angle between the tangents drawn through the point \((-2,-1)\) to the parabola \(y^2=4 x\) is \(\theta\), then \(\tan 2 \theta=\)

Which of the following sets of reagents convert aniline to chlorobenzene ?