Question 1 (a) An unknown compound, X, has the molecular formula C9H8O4. A student used a back titration to determine the percentage purity in a sample of X. The student reacted 0.200g of X with 30.0 cm³ of 0.1 mol dm-³ sodium hydroxide which was in excess. 1 mole of X reacted with 2 moles of sodium hydroxide. The excess sodium hydroxide required 11.7cm³ 0.1mol dm-³ hydrochloric acid for neutralisation. Deduce the percentage purity of compound X. You must show all steps in your answer. (b) The volume of 30.0 cm³ of sodium hydroxide was measured using a Class A burette. These measurements have a precision of ±0.1 cm³. Calculate the percentage uncertainty and absolute uncertainty in the volume of sodium hydroxide.

Question 1 (a) An unknown compound, X, has the molecular formula C9H8O4. A student used a back titration to determine the percentage purity in a sample of X. The student reacted 0.200g of X with 30.0 cm³ of 0.1 mol dm-³ sodium hydroxide which was in excess. 1 mole of X reacted with 2 moles of sodium hydroxide. The excess sodium hydroxide required 11.7cm³ 0.1mol dm-³ hydrochloric acid for neutralisation. Deduce the percentage purity of compound X. You must show all steps in your answer. (b) The volume of 30.0 cm³ of sodium hydroxide was measured using a Class A burette. These measurements have a precision of ±0.1 cm³. Calculate the percentage uncertainty and absolute uncertainty in the volume of sodium hydroxide.

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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