Identify the incorrect pair from the following:

Which one of the following is used in the preparation of styrene?

$A$ horizontal uniform glass tube of $100 \ cm$ length, sealed at both ends, contains a $10 \ cm$ mercury column in the middle. The initial temperature and pressure of air on either side of the mercury column are $31^{\circ} C$ and $76 \ cm$ of mercury, respectively. If the air column at one end is kept at $0^{\circ} C$ and the other end at $273^{\circ} C$, then the pressure of the air at $0^{\circ} C$ is (in $cm$ of $Hg$):

In the equation $log\, S = log\, C + Z\, log\, A$,what does $S$ represent?

During cell division,sometimes there is a failure of separation of sister chromatids or homologous chromosomes. This event is called

$A$ particle is released from a height $H$. At a certain height,its kinetic energy is half of its potential energy with reference to the surface of the earth. The height and speed of the particle at that instant are respectively: