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14 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 1 2 3 4 Fe Cl 3 (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: I 2 + Starch I 2 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.