Confusion about reaction order HCl + Mg

Alright this is a simple enough experiment, varying concentrations of HCL with magnesium ribbon. Problem is the results I obtained signal a reaction which is close to first order (about 1.2). However on the internet numerous sites report the order of reaction as 2 with the rate being:
rate = k [HCL]^2

I'm fairly confident the order with respect to HCL and the overall order leans more so to 1st order (obviously not perfect 1st order), but for piece of mind can anyone confirm this?

Reply 1

Lucy

cipapfatso

It is definitely 2 :smile:

. However if you did get 1 (assuming that you are doing this for coursework) you will still get the marks as long as you analyse your results/graphs properly. You will not lose marks if you didn't get an order of 2 (apparently if you choose a continuous experiment, the results are slightly more unreliable than if you use an initial rates method). I would also suggest a mechanism for the rate determining step. Just stick to fulfilling the coursework criteria and you'll be fine :smile: