Which of the following is a favourable factor for cation formation?

The structural formula of $2$-methyl-$2$-butene is:

$S_1, S_2, \ldots, S_{10}$ are the speakers in a conference. If $S_1$ addresses only after $S_2$,then the number of ways the speakers address is

What is known as 'Butter of Tin'?

In the given potentiometer circuit,the length of the wire $AB$ is $3 \, m$ and its resistance is $R = 4.5 \, \Omega$. The length $AC$ for no deflection in the galvanometer is ................ $m$.

Which one of the following gives a straight line for Freundlich adsorption isotherm?