In an elastic collision of two particles,which of the following quantities is conserved?

For the following cell reaction,$Ag|Ag^{+}|AgCl|Cl^{-}|Cl_2, Pt$
$\Delta G_f^{\circ}(AgCl) = -109 \ kJ / mol$
$\Delta G_f^{\circ}(Cl^{-}) = -129 \ kJ / mol$
$\Delta G_f^{\circ}(Ag^{+}) = 78 \ kJ / mol$
The $E^{\circ}$ of the cell is:

Two concentric hollow spherical shells have radii $r$ and $R$ $(R \gg r)$. $A$ charge $Q$ is distributed on them such that the surface charge densities are equal. The electric potential at the centre is

The energy-releasing metabolic process in which substrate is oxidized without an external electron acceptor is called:

Which of the following fluorides does not exist?

........ of a reaction cannot be determined experimentally.