EBK A SMALL SCALE APPROACH TO ORGANIC L
4th Edition
ISBN: 9781305446021
Author: Lampman
Publisher: CENGAGE LEARNING - CONSIGNMENT
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Chapter 2, Problem 3Q
Interpretation Introduction
Interpretation:
The reason for the low recovery of the crystal in the experiment performed by crystallization of biphenyl needs to be explained, if the sample weigh 0.5 g with 5% impurity and after crystallization the crystal dried and weigh 0.02 g.
Concept Introduction:
Organic compounds are mainly covalent compounds in which C-C, C-H and C-X bonds are present. Here, 'X' indicates heteroatom which is present in
A polar covalent molecule will be soluble in water whereas a non-polar covalent compound will be insoluble in water based on the concept of "Like dissolves like". Some of the polar compounds are also not soluble in water as they cannot form hydrogen bonding with water molecules.
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A student performs a crystallization on an impure sample of biphenyl. The sample weighs 0.5 g and contains about 5% impurity. Based on his knowledge of solubility, the student decides to use benzene as the solvent. After crystallization, the crystals are dried and the nal weight is found to be 0.02 g. Assume that all steps in the crystallization are performed correctly, there are no spills, and the student lost very little solid on any glassware or in any of the transfers. Why is the recovery so low?
5.0 mL of 1-butanol was mixed with 10 mL of HCl. The reaction was put on an ice bath and 4 mL of concentrated sulfuric acid was added. This mixture was refluxed for 45 min and then the product was co-distilled with water using a simple distillation apparatus. Water and the product are immiscible.
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What is the nucleophile in this reaction?
What is the role of H2SO4 in this reaction?
Calculate the theoretical yield for this reaction. Give your answer in grams.
Select the following statements that can be said about the reaction shown.
Using recrystallization techniques, a student attempts to purify 0.50 g of compound H. Based on the solubility of H in the chosen solvent at collection temperature, the maximum percent recovery is 82%. The student obtains 0.396 g of purified crystals. What is their percent recovery?
Group of answer choices
41%
64%
79%
82%
97%
none of these
Chapter 2 Solutions
EBK A SMALL SCALE APPROACH TO ORGANIC L
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