CHE 140/170 Handout – Electrolytes
Electrolytes
(ionic/covalent, nomenclature, salt/acid/base, strong/weak/non, dissociation in water)
We have lots to learn with electrolytes!
First, is it really an electrolyte or is a nonelectrolyte? Second, can we classify the electrolyte
as an acid or a base? Third, is the acid or base strong or weak? Finally, what chemical equation shows how the electrolyte breaks
apart into ions? Let’s get started!
First step, how do we determine if an electrolyte or a nonelectrolyte?
Electrolytes form ions in solution, so as long as you can classify
as ionic or covalent, this is easy! All covalent compounds are nonelectrolytes (as long as not acids or bases) as they do not form ions
in solution. As long as ionic compounds are soluble, they are classified as electrolytes. Practice this by identifying if the below
compounds are ionic or covalent and then by filling in the third column of the table. Why not review nomenclature by completing the
first two columns as well?
1. Al(ClO3)3 __________________
ionic
2. CH3CH2OH __________________
covalent
Second, we need to determine if any of the ionic compounds are acids or bases.
3. NH4NO3 __________________
ionic
For those that are not, the salts, we need to determine
which are insoluble. How is this done? Well, first answer the following.
4. What is the Brønsted-Lowry definition of an acid? capable of donating protons
5. What is the Brønsted-Lowry definition of a base? capable of accepting protons
For salts, look at a solubility table if you do not have the solubility of a particular salt memorized. Go ahead and fill in the fourth
column with acid, base or electrolyte. For salts, you can put strong for soluble ones and non for insoluble ones. Just leave a space for
“strong” or “weak” in front of the ones classified as acids or bases.
Third, we now need to classify acids and bases as either strong or weak.
Remember this is based on how many ions we get in
solution. Strong indicates that all ions are formed, whereas weak indicates that a mixture of ions and molecules (or a mixture of
broken apart and stayed together) are in solution. This is different from insoluble salts. Yes, insoluble salts stay together, but they do
not go into solution. The weak acids and bases that stay together are in solution! So, how do we know if strong or weak? Must
memorize all of the strong acids and bases. If not strong, then weak.
6. What are the formulas for all six of the strong acids? HCl, HBr, HI, HNO3, H2SO4, HClO4
7. What are the twelve strong bases? all alkali and alkaline earth metal hydroxides
Finally, we have to write out the chemical equation that shows the dissolving process (reaction) in water in the last column.
Remember to use the proper arrow!
Electrolytes key.docx
Page 1 of 3
CHE 140/170 Handout – Electrolytes
(classify as acid or base
instead if appropriate)
strong, weak, or
non; acid, base or
electrolyte
reaction in water (use the proper arrow –
can omit states), if none write N.R.
N.R.
ionic or covalent?
compound formula
compound name
N2H4
dinitrogen
tetrahydride
covalent
nonelectrolyte
NH3
ammonia
base
weak base
H2SO4
sulfuric acid
acid
strong acid
H2SO4 → 2 H+ + SO42–
Ca(OH)2
calcium hydroxide
base
strong base
Ca(OH)2 → Ca2+ + 2 OH–
Cu2CrO4
copper(I)
chromate
ionic
nonelectrolyte
H3PO4
phosphoric acid
acid
weak acid
Al(ClO3)3
aluminum
chlorate
ionic
strong
electrolyte
Sn3(PO4)2
tin(II) phosphate
ionic
nonelectrolyte
Fe(OH)2
iron(II)
hydroxide
ionic
weak base
Fe(OH)2
(NH4)3PO4
ammonium
phosphate
ionic
strong
electrolyte
(NH4)3PO4 → 3 NH4+ + PO4
CH3CH2OH
ethanol
covalent
nonelectrolyte
FeCr2O7
iron(II)
dichromate
ionic
strong
electrolyte
FeCr2O7 → Fe2+ + Cr2O72–
P4
phosphorous
covalent
nonelectrolyte
N.R.
Electrolytes key.docx
NH3 + H2O
NH4+ + OH–
N.R.
(insoluble, sits undissolved on bottom)
H3PO4
H+ + H2PO4–
Al(ClO3)3 → Al3+ + 3 ClO3–
N.R.
(insoluble, sits undissolved on bottom)
Fe2+ + 2 OH–
N.R.
(goes into solution as whole molecules)
Page 2 of 3
CHE 140/170 Handout – Electrolytes
compound formula
compound name
(classify as acid or base
instead if appropriate)
strong, weak, or
non; acid, base or
electrolyte
CuCO3
copper(II) carbonate
ionic
nonelectrolyte
Pb(NO3)4
lead(IV)
nitrate
ionic
strong
electrolyte
Pb(NO3)4 → Pb4+ + 4 NO3–
Ba(OH)2
barium hydroxide
base
strong base
Ba(OH)2 → Ba2+ + 2 OH–
CaSO4
calcium
sulfate
ionic
nonelectrolyte
HCl
hydrochloric acid
acid
strong acid
CH3CO2H
acetic acid
acid
weak acid
CH3CO2H
Co(NO3)2
cobalt(II) nitrate
ionic
strong
electrolyte
Co(NO3)2 → Co2+ + 2 NO3–
Cl2O
dichlorine
monoxide
covalent
nonelectrolyte
RbOH
rubidium hydroxide
base
strong base
H2CO3
carbonic acid
acid
weak acid
PF5
phosphorous
pentafluoride
covalent
nonelectrolyte
N.R.
NH4NO3
ammonium
nitrate
ionic
strong
electrolyte
NH4NO3 → NH4+ + NO3–
ionic or covalent?
Electrolytes key.docx
reaction in water (use the proper arrow –
can omit states), if none write N.R.
N.R.
(insoluble, sits undissolved on bottom)
N.R.
(insoluble, sits undissolved on bottom)
HCl → H+ + Cl–
CH3CO2– + H+
N.R.
(goes into solution as whole molecules)
RbOH → Rb+ + OH–
H2CO3
H+ + HCO3–
Page 3 of 3