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the table and specify the direction of the equilibrium shift (arrow to the right or

to the left).

Then add 1 drop of concentrated KNCS solution to the second tube. Record

the observed discoloration in the table and specify the direction of the equilib-

rium shift. Add a little crystalline KCl tothe third tube. Compare the color of

the resulting solution with the color of the solution in the fourth tube, which

you leave for comparison. Record the change in color and indicate the direction

of the chemical equilibrium shift. Is the chemical equilibrium shifted in accor-

dance with the Le Chatelier principle? Make a general conclusion.

Fill out the table in the laboratory log:

№

Added to the tube Change in the intensity

of the coloring

Output – the direction of the

displacement of the equilibrium

Fe Cl

(l)

KNCS (l)

KCl (s)

–

Experiment 2. Displacement of chemical equilibrium with temperature

change.

Pour 5 drops of starch, add 5 drops of iodine solution in each of two test

tubes. Add 2 ml of distilled water to each tube. Record the observations (the

color of the resulting solution). Heat one of the tubeson the spirit lamp. How

does the color of the solution change in a heated test tube? Write observations in

the laboratory journal. Cool the heated test tube. What’s happening? Write the

equation of the studied equilibrium:

+ Starch

Starch

dark yellow

blue

Draw a conclusionbased on the results of observations. What type of heat

effect does this reaction belong to?

LESSON 7.

CHEMICAL KINETICS. CATALYSIS.

Required base level.

The rate of chemical reaction. Factors affecting the reaction rate. Law of the

acting masses. The rule of Vant-Hoff.

Questions for the preparation for the lesson.

1. Average rate of chemical reaction. Kinetic curves.