Dinitrogen and dihydrogen react with each other to produce ammonia according to the following chemical reaction:
${\mathrm{N}}_2\left(\mathrm{g}\right)+3{\mathrm{H}}_2\left(\mathrm{g}\right)\to 2{\mathrm{NH}}_3\left(\mathrm{g}\right)$
(i) Calculate the mass of ammonia produced if $2.00\times 10^3 \mathrm{g}$ dinitrogen reacts with $1.00\times 10^3 \mathrm{g}$ of dihydrogen.

(ii) Will any of the two reactants remain unreacted?

(iii) If yes, which one and what would be its mass?

Assign oxidation number to the underlined element in each of the following specie:

${\mathrm{NaH}}_2\underline{\mathrm{P}}{\mathrm{O}}_4$.

Assign oxidation number to the underlined element in each of the following specie:

$\mathrm{NaH}\underset{-}{\mathrm{S}}{\mathrm{O}}_4$.

Assign oxidation number to the underlined element in each of the following specie:

${\mathrm{H}}_4{\underline{\mathrm{P}}}_2{\mathrm{O}}_7$. 

Assign oxidation number to the underlined element in each of the following specie:

${\mathrm{K}}_2\underline{\mathrm{Mn}}{\mathrm{O}}_4$.

Assign oxidation number to the underlined element in each of the following specie:

$\mathrm{Ca}{\underline{\mathrm{O}}}_2$. 

Assign oxidation number to the underlined element in each of the following specie:

$\mathrm{Na}\underline{\mathrm{B}}{\mathrm{H}}_4$ 

Assign oxidation number to the underlined element in each of the following specie:

${\mathrm{H}}_2{\underline{\mathrm{S}}}_2{\mathrm{O}}_7$. 

Assign oxidation number to the underlined element in each of the following specie:

$\mathrm{KAl}{\left(\underline{\mathrm{S}}{\mathrm{O}}_4\right)}_2.12 {\mathrm{H}}_2\mathrm{O}$.