91影视

The Ostwald process is a chemical reaction that produces nitric acid (${\text{HNO}}_{\text{3}}$ ). Wilhelm Ostwald invented the method, which he patented in1902. The Ostwald process is a cornerstone of contemporary chemical manufacturing, and it provides the primary raw material for the most prevalent type of fertiliser.

(a)

Stepincludes the disproportionation of nitrogen from oxidation state$\left(IV\right)$to$V$and$II$.

Disproportionation is a redox process in which one compound converts to two different compounds out of which one has a higher oxidation state, and the other one a lower oxidation state than the starting compound.

Therefore, it is disproportionation.

(b)

Combine the given three reaction into one reaction 鈥�

$$\begin{gathered} 4{\text{NH}}_3\left(g\right)+5{\text{O}}_2\left(g\right)鈫�4\text{NO}\left(g\right)+6{\text{H}}_2\text{O}\left(g\right) \\ 2\text{NO}\left(g\right)+{\text{O}}_2\left(g\right)鈫�2{\text{NO}}_2\left(g\right) \\ 3{\text{NO}}_2\left(g\right)+{\text{H}}_2\text{O}\left(l\right)鈫�2{\text{HNO}}_3\left(aq\right)+\text{NO}\left(g\right) \\ \stackrel{炉}{4{\text{NH}}_3\left(g\right)+8{\text{O}}_2\left(g\right)+6\text{NO}\left(g\right)+6{\text{NO}}_2\left(g\right)+3{\text{H}}_2\text{O}\left(\text{l}\right)鈫�6\text{NO}\left(g\right)+6{\text{H}}_2\text{O}\left(g\right)+6{\text{NO}}_2\left(g\right)+4{\text{HNO}}_3\left(aq\right)} \\ 4N{H}_3\left(g\right)+8O_2\left(g\right)+3{\text{H}}_2\text{O}\left(\text{l}\right)鈫�6{\text{H}}_2\text{O}\left(\text{g}\right)+4{\text{HNO}}_3(\text{aq}) \end{gathered}$$

Therefore, the overall reaction is obtained.

(c)

The formula is 鈥�

$$\begin{gathered} 螖H_{rxn}^o=螖H_{products}^o-螖H_{reac\tan ts}^o螖H_{rxn}^o \\ =\left[4mol路螖H_{HN{O}_3,aq}^o+6mol路螖H_{H_{2}O,g}^o\right]-\left[4mol路螖H_{N{H}_3,g}^o+8mol路螖H_{O_{2,g}}^o+3mol路螖H_{\left.H_{2}O,l\right]}^o\right] \end{gathered}$$

Substitute the values and calculate 鈥�

$$\begin{gathered} 螖H_{rxn}^o=[4脳(-206.57kJ/mol)+6mol脳(-241.826kJ/mol\left)\right] \\ -[4mol脳(-45.9kJ/mol)+8路0kJ/mol+3脳(-285.840kJ/mol\left)\right] \\ 螖H_{rxn}^o=-1236kJ/mol \end{gathered}$$

Therefore, the value obtained as $-1236kJ/mol$.