Which of the following statements is correct for a
reversible process in a state of equilibrium ?

Because of lanthanoid contraction, which of the
following pairs of elements have nearly same atomic
radii ? (Nubmers in the parenthesis are atomic
numbers).

Which of the following processes does not involve
oxidation of iron ?

A mixture of gases contains H₂ and O₂ gases in the
ratio of 1 : 4 (w/w). What is the molar ratio of the
two gases in the mixture ?

Cobalt (III) chloride forms several octahedral
complexes with ammonia. Which of the following
will not give test of chloride ions with silver nitrate
at 25ºC ?

The reaction