Write a formula for the following compound:

Chromium(III) oxide

Consider the reactions:
(a) $6\mathrm{C}{\mathrm{O}}_2\left(\mathrm{g}\right)+6{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)\to {\mathrm{C}}_6\mathrm{}{\mathrm{H}}_{12}{\mathrm{O}}_6\left(\mathrm{a}\mathrm{q}\right)+6{\mathrm{O}}_2\left(\mathrm{g}\right)$
(b) ${\mathrm{O}}_3\left(\mathrm{g}\right)+{\mathrm{H}}_2{\mathrm{O}}_2\left(\mathrm{l}\right)\to {\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)+2{\mathrm{O}}_2\left(\mathrm{g}\right)$

Why it is more appropriate to write these reactions as :
(a) $6\mathrm{C}{\mathrm{O}}_2\left(\mathrm{g}\right)+12{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)\to {\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6\left(\mathrm{a}\mathrm{q}\right)+6{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)+6{\mathrm{O}}_2\left(\mathrm{g}\right)$
(b) ${\mathrm{O}}_3\left(\mathrm{g}\right)+{\mathrm{H}}_2{\mathrm{O}}_2\left(\mathrm{l}\right)\to {\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)$
Also, suggest a technique to investigate the path of the above (a) and (b) redox reactions.

How do you count for the following observation?

Though alkaline potassium permanganate and acidic potassium permanganate both are used as oxidants, yet in the manufacture of benzoic acid from toluene we use alcoholic potassium permanganate as an oxidant, Why? Write a balanced redox equation for the reaction.
 

How do you count for the following observation?

When concentrated sulphuric is added to an inorganic mixture containing chloride, we get colourless pungent-smelling gas $\mathrm{HCl}$ but if the mixture contains bromide then we get the red vapours of bromine. Why?