Answer:
[tex]r_{NH_3}=140torr/h[/tex]
Explanation:
Hello,
In this case, the undergoing chemical reaction is:
[tex]N_2H_4 (g) + H_2 (g) \rightarrow 2 NH_3[/tex]
Thus, in terms of pressures, the rate becomes:
[tex]-r_{N_2H_4}=\frac{1}{2} r_{NH_3}[/tex]
Thus, the rate of change for the partial pressure of ammonia turns out:
[tex]r_{NH_3}=2*(-r_{N_2H_4})\\r_{NH_3}=2*[-(-70torr/h)]\\r_{NH_3}=140torr/h[/tex]
The rate of decrease of partial pressure of urea is taken negative as it is a reactant whereas ammonia a product which has 2 as its stoichiometric coefficient.
Best regards.