Searle’s bar experiment measures thermal conductivity by comparing temperature differences near the heat source and at the ends. However, since the temperatures at the unheated end/heated end often equalize at the beginning/end, the experiment may seem to take an indefinite time to yield results because you can't divide by zero, and I know for a fact that fraction can't be zero so often.

I want to synthesize methyl 3,5-dibromobenzoate (3,5-dibromobenzoic acid methyl ester).

This can be synthesized from the corresponding benzoic acid, ester, or aldehyde, which are all meta- directing. However, they strongly deactivate the benzene ring and make bromination difficult. Even if the first bromination is achievable, i cannot find any papers on how to do the second one.

I don't have access to an already bromo- substituted benzene compound.

Is there an easier synthetic route? I am struggling in finding any papers for reference.

I am very new to Organic Chemistry and although it seems like an easy target I still find it extremely difficult.

I am investigating how different transition metal catalysts (with different charges) affect the rate of reaction between Sodium thiosulfate and Iron(III) Nitrate. My catalysts were Ag(I)NO3, Cu(II)SO4, and Fe(III)Cl3. I observed the reaction from above and recorded the time it took for the cross at the bottom of the reaction became visible.

first of all, since I am not changing concentration, how do I find rate of reaction?

Also, I am having a hard time understanding what is happening.
CuSO4 was fastest (average of about 10.83 sec for the cross to appear)despite it being +2., and the other two (+1 and +3) were about the same to each other (around 56seconds). I don't understand the pattern, and what is affecting this.
can someone explain why CuSO4 was a better catalyst and why the other two didn't show much difference to each other? I have no clue what is going on and how exactly the catalysts impacted the reation...

Please help me. Thank you in advance.

I gave chiralic a molesnack, nice help

Yes, nice answer to an 18 years old post , dug out by a newcomer necroposter, probably using ChatGPT to generate reasonably looking answer

 I gave chiralic a molesnack, nice help