2nd Order Reaction - Units of Volume is in molarity?

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The discussion focuses on the reaction order of iodide ion oxidation by persulphate ion, specifically examining the validity of two equations related to concentration and volume in the context of a lab experiment. There is confusion regarding the units of concentration and volume, as the lab demonstrator states that the volume (V) is measured in mol/L, which contradicts standard volume units typically expressed in mL or L. Participants note an inconsistency in the equations that could lead to different values of the rate constant (k2) due to the incorrect relationship between concentration ([A]) and volume (V). To resolve this, it is suggested that the equations should incorporate a constant of proportionality, indicating that if [A] is proportional to V, the second equation should reflect this relationship accurately.
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This experiment investigates the reaction order of iodide ion oxidation by persulphate ion. Confusion about units in lab manual.
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This experiment investigates the reaction order of iodide ion oxidation by persulphate ion. The above image is my pre lab manual. Are the two equations boxed in blue valid? This seems to imply that that the units of [A] is the same as the units of V. But units of concentration being equal to the units of volume?? According to my lab demonstrator, the units of V in this case is in mol/L, which I haven't seen before for a unit of volume. V is also the titre value, which is from the titration - units of volume should be in mL/L etc. in my opinion.

Can someone please provide some insight on this? I can provide more details about the lab if needed. Thanks!
 
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You are right that there is an inconsistency; if you use the two equations to analyse your results, you will get different values of k2, with different units. As the text says, [A] is proportional to V, so you need to know the constant of proportionality. If [A] = qV, then the second equation needs to have 1/qV instead of 1/V. (The second term on the RHS is a ratio, and q will cancel out.)
 
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