[hni19]

For one of term-ending labs, we must determine an unknown substance.

The process for this lab will be:
We are given an unknown substance, we know it is ionic and white.
Put the substance into a Styrofoam calorimeter, filled with water, and record the change in temperature.
Determine what is the unknown.

I have tried performing this with theoretical data, but I can't seem to figure out how to determine the final answer.

For more information, here is a copy of the handout given. (I believe I have said all but...)
https://www.dropbox.com/s/ckuwk0976a2li79/SCH4U/2011%202012%20Summative%20Part%201.doc

[Honclbrif]

Are you having trouble calculating the enthalpy of solution, or are your results not making any sense/not matching standard values?

[hni19]

Are you having trouble calculating the enthalpy of solution, or are your results not making any sense/not matching standard values?

The result of the lab should be the discovery of the mystery substance (So molar mass is not known)

Here is an example of my theoretical calculations: (Not actual values, as lab not performed)
Assume rise of 1K of 100mL of water, after adding 1g of mystery substance)
q=mc(d)T
q=100*4.18*1
q=418
since (d)H = -q
(d)H=-418
So i found the enthalpy change, but do not know how to procede beyond this point.

Determine molar enthalpy(?)
(d)H=n(d)Hx (to do this will require n, which is gotten from n=m/M (dont know M)

This was my attempt at solving but, as you can see, did not work...

[UG]

Surely you will be given a list of all the possbile compounds and their enthalpy of solution values?

[hni19]

Sadly, to my knowledge, no :/.

[hni19]

Slight update. It is possible that we will be given a list of possible solids, so now through guess and check, molar mass could be used.

However, Im not sure if enthalpy of dissociation will be given...Is that possible to determine?