Answer:
Group VII has the most reactive elements
Yes, S-blocks are metals except for helium and hydrogen. The S-block metals are shiny, silvery and relatively soft, although they can easily lose electrons. Helium and hydrogen have valence electrons but also lack some similar properties as the other metals.
Oxidation is the loss of electrons and corresponds to an increase in oxidation state. Reduction is the gain of electrons and corresponds to a decrease in oxidation state. Balancing redox reactions can be more complicated than balancing other types of reactions because both the mass and charge must be balanced. Redox reactions occurring in aqueous solutions can be balanced by using a special procedure called the half-reaction method of balancing. In this procedure the overall equation is broken down into two half-reactions: one for oxidation and the other for reduction. The half-reactions are balanced individually and then added together so that the number of electrons generated in the oxidation half reaction is the same as the number of electrons consumed in the reduction half-reaction.
The equilibrium constant expression for this reaction that takes place in water and involve ions can be written as K= [H_3 O^+ ][OH^- ]/([H_2 O] ^2 ). But the concentration of undissociated water, H_2 O is much larger than the concentration of the ions that is essentially remains constant. Therefore, we can include it in the equilibrium constant. The resulting new equilibrium constant can be written: K_W= [H_3 O^+ ][OH^- ].
