"Grandpa" wrote in message
news:BREai.307$or4.20@trnddc06...
Ook wrote:
Labor can't replace material. Its called a "sacrificial" anode for a
good
reason. See he
http://www.waterheaterrescue.com/pages/WHRpages/English/Longevity/water-heater-anodes.html

--
Grandpa
Why do they call it an anode?
http://en.wikipedia.org/wiki/Anodes


I know what an anode is. I also know what a cathode is. But that doesn't
answer my question....I stick this rod in the middle of my water heater -
what makes it an anode, and not a cathode?
Did you read down to the part where it says "sacrificial anode" or just
skip it? It says:
"Sacrificial anode

In cathodic protection, a metal anode that is more reactive to the
corrosive environment of the system to be protected is electrically linked
to the protected system, and partially corrodes or dissolves, which
protects the metal of the system it is connected to. As an example, an
iron or steel ship's hull may be protected by a zinc sacrificial anode,
which will dissolve into the seawater and prevent the hull from being
corroded. Sacrificial anodes are particularly needed for systems where a
static charge is generated by the action of flowing liquids, such as
pipelines and watercraft."

--
Grandpa

I read it. It still doesn't explain why it's not a "sacrificial cathode".