The rate of disappearance of HI in the reaction 2HI(g) $\rightarrow$ I₂(g) + H₂(g) is shown in the following figure. What is the instantaneous rate of this reaction at t = 5 s?

Question

Quizplus · Accepted Answer

To determine the instantaneous rate at t = 5 s, we need to find the slope of the tangent line to the curve at that point. One way to do this is to draw a line tangent to the curve at t = 5 s and calculate its slope.

Using this method, we can estimate that the tangent line intersects the y-axis (i.e. HI concentration) at around 0.16 M (by extrapolating the line backwards). The initial concentration of HI is 0.2 M. Therefore, the change in HI concentration over the time interval from t = 0 s to t = 5 s is approximately 0.04 M.

Dividing this by the time interval, we get the average rate of the reaction over that interval:

average rate = (0.04 M)/(5 s) = 0.008 M/s

This is equivalent to the slope of the tangent line at t = 5 s. Therefore, the instantaneous rate of the reaction at t = 5 s is approximately 0.02 M/s.

Therefore, the answer is C.

The Rate of Disappearance of HI in the Reaction 2HI(g) →\rightarrow→

The Rate of Disappearance of HI in the Reaction 2HI(g) $\rightarrow$