Reaction Intermediate

The initial concentration of hydroiodic acid is 100 mmol/L but after 500 s it is 17 mmol/L. What is the rate? (note the products of this reaction are hydrogen and iodine gas)

The following initial rate data was collected for the reaction, A + 2B $\longrightarrow$ products

B. Find the rate constant

The following initial rate data was collected for the reaction, 2 NO + O$_2$ $\longrightarrow$ 2NO$_2$

[NO$_2$]$^X$[O$_2$]$^Y$

For the proposed mechanism below, find the overall reaction, identify the intermediates, then determine the rate law.

$CL_2~\leftrightharpoons~2~Cl$

$2~Cl~+2~NO~\longrightarrow~2~NOCl$