My teacher gives us tables to fill out, and I am really confused about how to go

Question

My teacher gives us tables to fill out, and I am really confused about how to go about it. Usually she gives us a few bits of information, but I need to learn how to do the conversions on my own. A table usually looks like this (with some procedure text):

This table is an example for the formation of benzoin. The procedure involves .420 g thiamene HCl, 1.0 mL 10% NaOH, and 1.20 mL of benzaldehyde. I can fill in those things, but I don't know how to fill in the other blanks. For example, how do you calculate equiv (from any of the above)?

From here, how do I calculate theoretical yield? I know that I need to start with the limiting reagent, but how do I determine which one that is?

Thanks!!!! I can usually get help from my friends, but I need to know how to do these calculations (specifically equiv and mmol) on my own.

compound mp/bp, C MW (g/mol) equi mmol g density (g/mL) mL thiamine-HCl mp, 260 (dec) 337.3 (solid) XXX benzaldehyde bp, 178-179 1.044 NaOH, 10% (w/v) XXX 40.0    XXX

Explanation / Answer

1) mmol of a particular compound = weight of the compound / molecular mass

if the compound is liquid then, weight of the compound can be calculated from density

density = mass/volume; mass (weight of the compound) = density x volume

2) equivalents can be calculated from simplest mole ratio.

3) out of the all starting reagents, compound which is having lower equivalents is limiting reagent.

4) theritical yield = no. of moles of product x molecular weight of product.

here NaOH used as base, it is not involved in the reaction.

compound mp/bp, C MW (g/mol) equi mmol g= 103mg density (g/mL) mL thiamine-HCl mp, 260 (dec) 337.3 1 420mg/337.3=1.245 mmol 420 milligram (solid) XXX benzaldehyde bp, 178-179 106.12 9.48 1252.8/106.12 = 11.8 mmol 1.044x1.20 gram =1.2528 gram = 1252.8 mg 1.044 1.20 mL NaOH, 10% (w/v) XXX 40.0 10/40 = 0.25 mmol 10mg/1mL=1mL 10% NaOH XXX

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