Question

determine the solubility of benzoic acid in water and calculate its delta H (chemistry lab) ​

Answer 1

Answer:

As solubility is the concentration of a solute in a saturated solution you have to saturate a solvent with you solute and measure the resulting concentration. You can do this by:

1. Make sure you have a saturated solution of benzoic acid in water (with solid benzoic acid present). This can be achieved through stirring an excess of the solute in the solvent. If all solid is dissolved more should be added and ample time be given to allow equilibrium to be reached.
2. Withdraw sample and remove all remaining solid benzoic acid through filtration or centrifugation.
3. Dilute sample and determine concentration using an available method. Calculate the concentration of the saturated solution with the dilution factor used.

It's a good idea to perform the experiment in replicates and make sure conditions such as temperature is kept constant throughout the assay.

The molar enthalpy of combustion for benzoic acid is -3226.6 kJ/mol. The thermochemicasl equation is: 2C6H5COOH (l) + 15O2 -> 6H2O (l) + 14CO2 (g)ΔH= -3226.6 kJ/mol Given the heats of formation for liquid water is -285.5 kJ/mol and carbon dioxide is -393.5 kJ/mol, calculate the heat of formation of benzoic acid.

Answer 2

Explanation:

you understand.........