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What are we watching?
Record the equation of the corresponding reactions.

Starch Hydrolysis

Polysaccharide starch hydrolyzes under the action of
enzymes (saliva) and under the influence of acid. Since the
presence of an acid is possible in drilling fluids, gradual
hydrolysis with the formation of smaller pieces of starch, so-
called dextrin, up to complete hydrolysis to glucose may be
possible.
3
In a glass pour 10 cm of starch paste (from the
previous experiment), add 10 cm3 10% solution of sulfate
acid and boil. Every 2 min. sampled into test tubes. Each
sample is filled with 10% sodium hydroxide solution to a
neutral medium (according to a universal indicator) and an
alcoholic solution of iodine is added. If at the initial stage
we have a blue color, which is typical for starch, then, when
boiling, the color of the samples selected with iodine
solution changes first to violet, then becomes reddish-
brown, and then there is a complete discoloration of the
sample.
The remaining solution is boiled for another 3-5
minutes. and after cooling and neutralization add felted
liquid and heat. At the same time there is the formation of a
red Cu 2O precipitate, which is a characteristic reaction to
glucose, and indicates that the hydrolysis has passed
through.

Record the equation of the corresponding
reactions.
Hydrolysis of cellulose

3
Pour 4-5 cm of 70-80% solution of sulfate acid into
the test tube and lower the chopped strips of filter paper.