The process of setting of cement is an ...... process.

The lubricating action of an oil is more if it possesses:

Photographic films and plates have an essential ingredient of

Which of the following are not completely surface phenomena?

Identify the correct statements from the following.
$(i)$ In the oxidation of oxalic acid with $KMnO_4$ in acid medium,$Mn^{2+}$ acts as an autocatalyst.
$(ii)$ $CdS$ colloidal solution can be precipitated by the addition of $Cl^{-}$ ions.
$(iii)$ The gold numbers of three protective colloids $(A, B, C)$ are $0.03$,$25$,and $0.25$ respectively. Their protective power follows the order $A > C > B$.
$(iv)$ Physisorption is an irreversible process.

Indicator type silica gel used as a dehumidifier contains