October 07, 2014
Electrolytes vs Non-electrolytes
Electrolyte
Non-electrolyte
Definition Substances when
dissolved in water
conduct electricity.
Why
Identify
Substances when
dissolved in water DO
NOT conduct electricity.
Because when
dissolved in water ions
(+ and - charge) are
produced.
The 1st element will
start with a metal
(Found in group 1, 2 or
3) ex- NaCl
Because when
dissolved in water ions
ARE NOT produced.
The first element will
start with a non-metal
(found in groups 4-7)
ex- PCl3
The Basics on Electrolytes.mp4
Electrolyte dissociation
Def: The separation of a molecule into its atoms
Ex:
NaCl(s)
CaS(s)
Na
Ca
+2
+
(aq)
(s)
-
+
+
Cl (aq)
S
-2
(g)
How to determine if electrolyte dissociation will occur?
Look at 1st of compound.
1
st
element is a metal = electrolyte = electricity is produced
st
1 element is a non-metal = non-electrolyte = no electricity
*Elements starting with ‘H’ will conduct electricity.
Which examples will conduct electricity?
CaCl2
H2SO4
P2S3
KOH
SCl2
CCl4
October 07, 2014
Conduction capabilities
October 07, 2014
Types of electrolytes
Base
Acid
Definition
· · · pH less than 7 · · · pH greater · · · made of
than 7
metals bonded
· · · taste sour
to non-metals
· · · turn blue litmus · · · bitter,
(KCl, CaCl2,
slippery
paper RED
MgBr2)
·
·
·
turn
red
· · · when dissolved,
·
· · have no
litmus paper
separate into H+
effect
on litmus
and a negative ion BLUE
paper
· · · when
· · · (diagram)
· · · important in
dissolved,
· · · start with
human body
separate into
"H" (HCl, H2SO4)
(minerals), soil,
OH- and
fertilizer
positive ion
(diagram)
· · · end in
"OH" (NaOH,
Mg(OH)2
negative ion
· · · OH- and
positive ion
· · · made of
metals bonded
to non-metals
BRA (Blue -> Red
= Acid)
RBB (Red ->
Blue = Base)
have no effect
on litmus paper
Electrolyte · · · H+ and a
Litmus
paper
Salt
Found in
Fruits, cleaning
products, batteries
Recognize
H
Examples
Blood, cleaning Foods, human
products
body, soil
OH
NaOH
NaCl, KCl,
HCl
Exceptions
H2O
CH3COOH
From the molecular formula, how can you determine if a substance is a nonelectrolyte?
October 07, 2014
False acids and bases (organic molecules)
· molecules that may start with H or end in OH
but are NOT electrolytes
· these molecules contain carbon (C)
· they do not separate into ions, therefore do
not conduct electricity
· they are neutral
Ex. CH3 OH, C2 H5 OH, CH3 COOH
October 07, 2014
October 07, 2014
October 07, 2014