Illustrated Guide to Home Chemistry Experiments

292 DIY Science: Illustrated Guide to Home Chemistry Experiments

SBSTITUTIU oNS ANd modIfICATIoNS

• You may substitute a hotplate, kitchen stove burner,
  or similar heat source for the alcohol lamp or burner,
  which also eliminates the need for the tripod stand or
  ring stand and the wire gauze. If you use a hotplate or
  kitchen stove burner, place a large tin can lid or similar
  item between the burner and the beaker.


• You may substitute bolts, nuts, or other hardware
  items for the nails. Make sure that whatever items you
  use are iron or steel and not galvanized or otherwise
  plated with a substance other than iron or steel.


• You may substitute ordinary table salt for the sodium
  chloride.


• If you do not have a 1 M solution of sodium chloride on
  hand, weigh 5.85 g of sodium chloride, dissolve it in
  distilled or deionized water, and make up the solution
  to 100 mL.

6.epeat step 5 for test tube E. R

7. Set up the beaker on the tripod stand or ring stand, using
   the wire gauze to protect the beaker from direct flame.


8. Use test tube B to transfer about two test tubes worth of
   distilled or deionized water to the beaker.


9. Light the alcohol lamp or burner, and bring the water
   to a gentle boil. Continue boiling it gently for several
   minutes. The goal is to drive off all of the oxygen
   dissolved in the water.
   Place the second clean nail in test tube B.

Use the beaker tongs to fill test tube B with the boiled

water to the line you previously made on the test tube and

insert the stopper gently. You needn’t force the stopper

into place. The idea is simply to prevent the contents of

the test tube from being exposed to atmospheric oxygen.

Place the third clean nail in test tube C, and fill the tube

to near the rim with distilled or deionized water that has

not been boiled. Leave this test tube unstoppered.

Place the fourth clean nail in test tube D, and fill the tube

with solid sodium chloride until about half the length of

the nail is covered by the sodium chloride.

Use test tube E to transfer about two test tubes worth

of 1 M sodium chloride solution to the beaker. Bring the

sodium chloride solution to a gentle boil and continue

boiling it gently for several minutes to drive out dissolved

oxygen.

Place the fifth clean nail in test tube E, use the beaker

tongs to fill test tube E with the boiled sodium chloride

solution to the line you previously made on the test tube,

and insert the stopper gently. Again, seat the stopper

gently. All we want to do is prevent the contents of the

test tube from being exposed to atmospheric oxygen.

Place the sixth clean nail in test tube F, fill that test tube

with unboiled 1M sodium chloride solution, and return

the test tube to the rack. Leave it unstoppered.

Set the rack of six test tubes aside; check it under a strong

light after several hours or overnight to see if the nail in

one or more of the test tubes has begun rusting. Continue

checking the tubes periodically until it is evident that

rusting is or is not occurring in each of the tubes. Record

your observations for each of the tubes in Table 16-2.

TABLE 16-2: Observe the electrochemical oxidation of iron—observed data

Test tubeO 2 H 2 O naClAmount of oxidation

A l ¢ ¢ none···light···moderate···heavy···extreme

B ¢ l ¢ none···light···moderate···heavy···extreme

C l l ¢ none···light···moderate···heavy···extreme

D l ¢ l none···light···moderate···heavy···extreme

E ¢ l l none···light···moderate···heavy···extreme

F l l l none···light···moderate···heavy···extreme

dISpoSAL: The solid waste

material from this lab can be

disposed of with household waste

and the liquid waste material may

be flushed down the drain with

plenty of water.

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