Question

Properties of Solutes in Aqueous Solutions

Conductivity:

1. How does the increase in solute concentration affect the conductivity of that solution?

2. Comment on the differences in conductivity for tap water, distilled water, ethanol, and glacial acetic acid. Are there differences, why/why not?

3. You tested the conductivities of sodium chloride, calcium chloride, and aluminum chloride. What was the trend in conductivity for these three chloride salts and why?

Answer 1

Q1

the more ions in solution, the more free e- can flow, therefore increases conductivity

Q2

tap water = has ions fomr Mg2+, Ca+2, Na+, NO3- salts, PO4-3, et.c.. due to common salt/soil properties

vs. distilled water --> no ions, theoreticlaly speaking, it shoul have no ions

ethanol/glaciac acetic acid = those are "pure" that is, the impuritie spresent are not likely to be ions

Note that the conductivity of ethanol --> null, ethanol will dissolve inw ater, but will not increase the conductivity since no ions are formed.

glacial acetic acid --> favours slightly dissociation of acid, so it is a weak conductor

Q3

NaCl= 2 ions, Na+ + Cl-

CaCl2 )= Ca+2 + 2Cl- = 3 oins

AlCl3 = Al+3 + 3Cl- = 4 ions

therefore

the more ions --> stronger conductor

AlCl3 > CaCl2 > NaCl