Best* and are there answer choic
Question 1:
(a) Sulfurous acid: H2SO3
Sulfuric acid: H2SO4
(b) Nitrous acid: H2NO2
Nitric acid: H2NO3
Question 2:
To calculate the pH, based on concentration of H+ ions, there is one formula:

So the pH of this solution is

(the solution is basic).
Iron is left in the filter and salt solution (salt and water) passes into the cup.
Hope it helps
Depending if the reaction is a reversible or an irreversible one, the direction of the arrow will point in one direction or 2 directions from reactants to products.
Energy is released when a chemical bond forms