Crystallization of Benzoic Acid

[thE3nigma]

Hi there,

This may seem like weird question, but for my pre-lab this week I need to add along with intro and flow chart a table of reagents. now my only two reagents that I will be using is 2 g of crude Benzoic acid (including impurities) and water. in my table though, they ask for the # moles and density of applicable.

since my 2 grams of crude benzoic acid is not pure, should I still convert it into # moles. My thinking is that I should not. Also for water, since I do not know exactly how much I will have to add during the boiling process, I believe I should not add this either.

As for densities, since none were given in the lab manual - is it customary to use 1 g/mL for water and 1.32 g/mL for benzoic acid in its solid form?

Thanks.

 

[Borek]

I would convert benzoic to moles stating something like "maximum number of moles" to underline that it is not really true.

 

[thE3nigma]

That is what I was thinking should have been done. Thanks for the tip Borek.