2. (a) A helium gas (He) leak resulted in a rectangular vessel (200 cm x 20 cm x 10 cm) becoming pressurized at a temperature of 20 °C with 400 g of helium. Given that the van der Waals constants for helium (He) are: a (Latm mol) = 0.0341 b (L mol"') = 0.02370 (1) Calculate the pressure exerted by the helium gas in the vessel. (ii) Calculate the root mean square speed of a He atom at 20 °C. (b) A rescarcher wishes to obtain a glycoside (an organic compound) from an aqueous plant extract using the solvent extraction technique. She therefore performs the following steps: Step 1: An aqueous solution (100 mL) containing 7 g of the glycoside was shaken with 50 mL of ethyl acetate. Step 2: The resulting aqueous layer from Step 1 was further shaken with 50 mL of dichloromethane. Given that: Kp for the glycoside in ethyl acetate-water = 0.8 Kp for the glycoside in dichloromethane-water = 0.9 %3D

2. (a) A helium gas (He) leak resulted in a rectangular vessel (200 cm x 20 cm x 10 cm) becoming pressurized at a temperature of 20 °C with 400 g of helium. Given that the van der Waals constants for helium (He) are: a (Latm mol) = 0.0341 b (L mol"') = 0.02370 (1) Calculate the pressure exerted by the helium gas in the vessel. (ii) Calculate the root mean square speed of a He atom at 20 °C. (b) A rescarcher wishes to obtain a glycoside (an organic compound) from an aqueous plant extract using the solvent extraction technique. She therefore performs the following steps: Step 1: An aqueous solution (100 mL) containing 7 g of the glycoside was shaken with 50 mL of ethyl acetate. Step 2: The resulting aqueous layer from Step 1 was further shaken with 50 mL of dichloromethane. Given that: Kp for the glycoside in ethyl acetate-water = 0.8 Kp for the glycoside in dichloromethane-water = 0.9 %3D

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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