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Preparing Benzoic Acid Assessed Practical

Ok so I carried out this practical (p.g. 61):
http://www.ocr.org.uk/Data/publications/teacher_support_and_coursework_guidance/cquartetOCRTempFilex4D0cMSP1b.pdf

The mass I recorded was to 5 significant figures and I intended to write it to 3 significant figures on the container and in my observation thing. I asked my tutor and he said that 2 significant figures would be ok because it states "use 2.0 cm3 of...." and since it gives that to 2 significant figures, the mass could be given in that way too. Hence, I ended up writing to two significant figures on the container but EVERYONE I know has wrote it to 3 significant figures. Also, in the mark scheme it says
"makes and records all observations
and/or measurements in appropriat
detail and to the degree of precision
permitted by the techniques or
apparatus."

I'm unsure as to what to do, will I be able to change the mass on the container, if not then should I write it to 3 significant figures in my report or should I just stick to 2? Also, I got some melting points in the range 126-131 (as a whole). The actual melting point is 122 according to wikipedia. Will I lose a significant amount of marks for the inaccuracy?
Thank You
2 significant figures is fine. In all chem practicals i did i used 2 s.f. and plus if your teacher said use 2 sf then i say stick to it. doesnt matter if everyone did it to 3sf.
In answer to your second question..firstly you should bear in mind the wikipedia is a free source so it may be inaccurate itself. The mark scheme should/will allow for some variation in the temperatures you get and who knows it may even be in that range that you stated. You sholdnt lose a significant amount of marks if you dont get the exact figure (maybe 2-3 at most). and to be fair everyone loses a mark or two here and there so dont worry too much about it
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Zigi
OP
Thanx for the help, I was getting worried that I'd mess it up

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