ined compare with the amount given
in the tables of analysis?

Experiment No. 2

Water in Butter

Carefully weigh a clean, dry aluminum dish, place in it about 2 gms. of
butter, and weigh again. Record the weights. Place the dish containing
butter in the water oven for 5 or 6 hours and then weigh. The loss in
weight represents the water in the butter. Calculate the per cent of
water. Care must be taken to get a representative sample of the butter
to be tested; preferably small amounts should be taken with the butter
trier from various parts of the package.

Experiment No. 3

Ash in Flour

Place the porcelain dish containing flour from the preceding experiment
in a muffle furnace and let it remain until the organic matter is
completely volatilized. Cool, weigh, and determine the per cent of ash.
The flour should be burned at the lowest temperature necessary for
complete combustion.

Experiment No. 4

Nitric Acid Test for Nitrogenous Organic Matter

To 3 cc. of egg albumin in a test tube add 2 cc. of HNO_{3} (conc.) and
heat. When cool add NH_{4}OH. The nitric acid chemically reacts upon the
albumin, forming yellow xanthoprotein. What change occurs in the
appearance of the egg albumin when the HNO_{3} is added? Is this a
physical or chemical change? What is the name of the compound formed?
What change occurs on adding NH_{4}OH?

Experiment No. 5

Acidity of Lemons

With a pipette measure into a small beaker 2 cc. of lemon juice. Add 25
cc. of water and a few drops of phenolphthalein indicator. From the
burette run in N/10 KOH solution until a faint pink tinge remains
permanently. Note the number of cubic centimeters of KOH solution
required to neutralize the citric acid in the lemon juice. Calculate the
per cent of citric acid.

(1 cc. of N/10 KOH solution equals 0.00642 gm. citric acid. 1 cc. of
H_{2}O weighs 1 gm. Because of sugar and other matter in solution 1 cc.
of lemon juice weighs approximately 1.03 gm.)

1. What is the characteristic acid of lemons? 2. What is the salt formed
when the lemon juice is neutralized by the KOH solution? 3. Describe
briefly the process for determining the acidity of lemon juice. 4. What
per cent of acidity did you obtain? 5. How does this compare with the
acidity of vinegar?

Experiment No. 6

Influence of Heat on Potato Starch Grains

With the point of a knife scrape slightly the surface of a raw potato
and place a drop of the starchy juice upon the