Transcript Real World Experiment - York College of Pennsylvania

Ronnie Groller
and
EJ Habina
Intro
 The purpose of our experiment was to test water from
several different sources for hardness, ions, and pH.
Our samples were from a YCP tap, a Jackson St. tap,
the Codorus creek, and Dr. Peterman’s well.
Water Hardness
 “Hardness” is based on the concentration of Ca2+ and
Mg2+ ions in a sample of water. The harder the water,
the higher the concentration of ions. Hard water is not
necessarily harmful to humans, but it can leave stains
and mineral buildup on tubs and faucets. In our
experiment, we tested specifically for the Ca2+ ion.
Water Hardness Procedure
 To test for water hardness, each sample of water will be
titrated with an EDTA buffer solution, using calgamite
as the indicator.
Water Hardness Data
 The creek ended up being the hardest water, with an
average of 8.3mL of EDTA added to each sample. The
well water was second hardest, with 6.1mL added. Both
the YCP and Jackson St. tap water were very similar,
with 4.5mL and 4.4mL averaged respectively.
Ion Test
 We tested each sample for the presence of ions,
including chloride, sulfate, lead, and calcium. This was
done through a series of qualitative tests. The samples
were first boiled for concentration, and the substances
such as silver nitrate, barium nitrate, HCl, nitric acid,
and ammonium carbonate. If a precipitate formed
when these chemicals were added, the sample was
positive for the ion.
Ion Data
 All samples tested positive for chloride, sulfate, and
calcium, except for the creek water. The creek water
was positive for chloride and sulfate, but negative for
lead and calcium. All samples tested negative for lead.
(that’s a good thing!)
pH
 Testing for pH was quite simple. All we had to do was
calibrate the pH meter, and test each of our samples of
water. The creek water had the highest pH, at 8.03.
The Jackson St. tap was a close second at 8.02. The YCP
tap had a pH of 7.77, and Dr. Peterman’s well water
had the lowest pH at 7.70.
Thank You for Listening!