For the reaction $N_2 + 3H_2 \to 2NH_3$,which of the following represents the correct expression for $d[NH_3]/dt$?

Consider a gas phase reaction which occurs in a closed vessel: $2 \ A \rightarrow 4 \ B + C$. The concentration of $B$ is found to be increased by $5 \times 10^{-3} \ mol \ L^{-1}$ in $10 \ s$. The rate of disappearance of $A$ (in $mol \ L^{-1} \ s^{-1}$) is:

For the chemical reaction: $N_{2(g)} + 3H_{2(g)} \rightarrow 2NH_{3(g)}$,the rate of reaction can be expressed in terms of the concentration of $N_{2(g)}$,$H_{2(g)}$,or $NH_{3(g)}$ with respect to time. Identify the correct relationship between these rates.

Consider the reaction,$2 NO_{2(g)} \rightarrow 2 NO_{(g)} + O_{2(g)}$. In the figure below,identify the curves $X, Y$ and $Z$ associated with the three species in the reaction.

In a reaction $A_2B_{3(g)} \to A_{2(g)} + \frac{3}{2}B_{2(g)}$,the pressure increases from $60 \ torr$ to $75 \ torr$ in $2.5 \ min$. The rate of disappearance of $A_2B_3$ is ........ $torr \cdot min^{-1}$.

For the reaction $2P + Q \to R$. If the rate of appearance of $R$ is $0.5 \ mol \ L^{-1} \ h^{-1}$,then the rate of disappearance of $P$ and $Q$ are: